Honestly, I don't know.  I only got into PC 3 years ago.  But I would guess a giant PITA.  

I think that is my point.  Steam excels at keeping games compatible with new hardware, which means replacements are easy.  Given Steam BC, odds are I will update my computer before anything breaks. 

I love the idea of having the real legit hardware, there is something nice about playing old school, it was just a hassle.  Possible I had bad luck. 

Original hardware wins for experience, while emulation is just for convenience, especially in unique situations.  Like Shining Force III Scenario 2 and 3 having english roms.  I don't know how else to play scenario 2 and 3. 

Edit

As for cost, I think PC is way cheaper than building a collection of old games.  Shining Force III is $300 on Ebay, that is a GPU.  Skies of Arcadia on the DC is $150, that is hard drive.  Retro gaming is super expensive for games.  Canon Spike is $300, there is my CPU.  Luigi's Mansion on GC is $50, there is my PSU.  

I could easily build a computer far cheaper than collecting retro games/hardware.  

They are as cultists as console users 

Make with that information what you will 

The later part you are involving physical media vs digital media, I don't think it merits that kind of comparison at least for me, as to me physical media is by far superior to digital media so the price comparison has very little weight.

Even if a game is $300, which I clearly won't buy it, because that's ridiculous, I would still only consider the digital version if it's like $5, at most $10, as I really not value it much at all, most digital games I bought were between $1 to $5.

A great example, I just bought some NeoGeo Metal Slug games on PS4 for $4 each, where the NeoGeo physical version price could go beyond $10000 for some, so yeah, no brainer, but still needs to go as low as it was for me to consider it, as I never bothered buying them for $9 they usually sell for.

I think that having digital as an option is great, it also helps A LOT with preservation, but I really simply don't hold anywhere near the same kind of value between purchasing a physical or a digital game for them to hold any actual weight when compared to eachother.

But that's just me, and I know is not really the cheapest way to be involved with gaming.

I hadn't thought about it, I wonder if my preference for digital is because of my career.  I have moved 4 times in 12 years, including internationally.  Maybe I just got tired of packing stuff up.  

- Most PC games on Steam are also available on other PC stores. Steam isn't a monopoly. So it is your own choice for most titles if you buy them on Steam or in other PC stores (or for many older PC games on disc). 
- Many Steam games don't have any DRM. Those games will be still playable in case of the (very very unlikely) possibility that the Steam ecosystem leaves the market within the next decades
- Even without Steam as an active platform, the Steam client software would still exist (there are millions of copies ion the internet). So most Steam games which need the SteamWorks APIs to start, would still work in Steam offline mode.
- The Steam offline mode has no offline time limit for games (you can try it out by going offline and then change the calendar date of the system years or decades into the future)
- most popular Steam games with Steam-DRM would get cracks very fast that remove the Steam-DRM... heck, probably most popular Steam games are already cracked

Steam games don't NEED to be EMULATED, they are already PC games. You can save/backup/ZIP any file folder of your Steam library you want, if you don't trust Steam for a redownload.They aren't in copyprotected folders like many Microsoft-Store-games.

All you need to play the games in these folders is a cracked EXE-file, in some cases additionally a registry-entry which you can export. For DRM-free Steam games you only need the files in the game folder.

And why exactly do you give Nintendo, Sony and Microsoft a pass for that preservation issue? They are binding the digital games they offer to their platform accounts AND their gaming hardware. The emulation options are against their will and they are trying to stop emulation of their games as far as it is legally possible for them (Nintendo more aggressive than Sony and Microsoft).

Most GOG games work fine with the Heroic Game Launcher. Have you tried that?

That's definitely a big concern.

That's both expensive and troublesome to move around, and it only gets worse when you keep getting more stuff.

Collecting is also fun, tho, it makes me happy finally getting a game I was looking out for some time, and looking at them physically makes me happy too.

The kind of person I am is I only want to get something digital if super cheap but if the physical copy becomes an option I will buy it again for that. Even when I had free Gamepass for a month buying a new Laptop some years ago I played Ruiner. I stopped after a little but to spend $50 for the physical on PS4. I always prefer physical first. Sometimes I will double dip on a game physically or triple or more. But also If I have the game physical on one console I am ok to have it digital on another. Depending what came first I might keep it sealed not for monetary value. Example. I have Raiden III/IV on Switch (also have IV on 360) but they went on sale on SX for super cheap so got them digitally. The reverse of that is Ninja Gaiden II Black which launched digital only on Series X. I bought it there. It later came to PS5 physical so I bought that but still sealed. It's just so I have a physical version. I like something tangible I can hold.

For retro games. Take Blood Will Tell on PS2 for example. I can't buy the US version. It;s $400. I played the US version on PCSX2 emulator. Then bought the Japanese version. I don't have a Japanese PS2. It's just nice to own a physical copy tho. Will sometimes do that, US version too pricey, import a Japanese copy.

"The service Steam offers is a highly predatory one that needs to be regulated."

No, it isn't. Othan than that, the issue is real though. I just don't see how it could be solved. As long as DRM exists - and I just don't see DRM disappearing, as much as I'd love that to happen, someone will need to provide access to the games you've paid for. If Steam isn't around to provide access, then who is? Publishers? They topple over even easier, and realistically having to provide download service is probably quite inefficient to be done by publishers anyway. The competitors? Why would they do that, and which ones?

Perhaps a reasonable solution would be to require DRM to be patched out in x time after release or effectively ending support for a game.

For games without DRM though, this is not a huge issue even now. I suppose it would be reasonable to require that offline installers be provided for games without DRM though.