I think game preservation in general is going to get harder as planned obsolescence takes over. You can't get the Steam version of Fallout 3 running very well on Windows 10. I doubt a launch model PS5 or Series will last past 10 years of moderate playtime. CRTs will start dying in the next 10 to 15 years, forcing us CRT lovers to deal with the mess that modern monitors make of 16 and 8 bit games. 

But despite all this I think it will still be entirely possible for a dedicated enthusiast to play his games on somewhat original hardware for decades to come (provided he's willing to open his wallet). Saturn disks are rare, but ODE modules like MODE or Fenrir solve that problem. I'm willing to bet that there will eventually be a 3DS and DS cart emulator out there once all the carts finally die. Analogue makes excellent clones of SNES/Genesis/GBA, etc. that all act exactly like the original hardware. In 20 years, I bet there will be an FPGA Gamecube out there, and an FPGA PS2! 

I would take the care to make backups of my backups with any digital Nintendo games. Sony and Nintendo seem not to care all that much about keeping their digital stores up after 10 to 15 years. 

As far as going all digital goes, I sort of agree. I'm skipping PS5 this gen, because I know once my PS5 breaks all my games are unplayable. Instead I'm getting the big AAA games on PC, because I know I can fix my PC if it breaks. 

As for going all digital on Switch, I can't really agree. Nintendo is bound to take their servers offline one day. Joycons may break, but the Switch in general seems to be pretty sturdy thanks to being a gen and a half behind PS5/Series. Switch 2 is bound to be backwards compatible and likely still in production by 2033. So even if you give a Switch 2 a lifespan of 10 years of moderate play, I'm willing to bet Switch games will be playable on OG hardware until 2043. 

Not true. Digital stores shut down all the time, you can still download your games from the service to play the games. Eg: The Wii store closed and the games are still available for download.

Saying it will sooner happen isn't saying it has happened and is nothing more than a assumption. What store front has shut down where you cannot re-download already purchased content? 

And please, if you are going to throw examples, make sure that you actually tried it first and not listened to random people on the internet. The reason i am saying this is because some Youtuber i was listening to said that once the Wii store shut down, he wasn't able to redownload his games and made a full video about it which was completely false. I personally called Nintendo and they said that's false information, and that you will always have access to already purchase content.

The internet has span digital stores closing and losing content that it has scared people. Unless a company goes completely bankrupt, they have to obliged to people who have made purchases otherwise it will lead to law suits.

I agree.

Just wanted mention that NES carts are notorious for failing thanks to people blowing in them, and power cycling over and over again. I have 21 NES carts and five of them are insanely hard to get to start up. I would estimate that around 20% of NES carts sold in shops either have one foot in the grave or are dead already. But that's been a problem with the NES since the start. 

As for carts in general they are pretty damned sturdy like you said. Genesis/SNES/GBA/N64 carts all work fine and will outlast Series/PS5 launch hardware. :)

Doesn’t seem to be a problem with mine.
Also, if it was due to age, then you’d have expected the same fate to have befallen X & Y cartridges earlier, as those games pre-date the Gen3 remakes.