Paying to just play online is such a scummy practice... they already get 30% of every game/DLC they sell on PSN and physically, overpriced accessories etc.

Hardware-wise, consoles are more bang for the buck, but this quickly balances-out with everything being more expensive once you own one, so a PC is a much better deal for what you're paying regardless.

Back in 2016, Andrew House, then CEO of SIE, said this:

"I saw some data that really influenced me,” he said. “It suggested that there’s a dip mid-console lifecycle where the players who want the very best graphical experience will start to migrate to PC, because that’s obviously where it’s to be had. We wanted to keep those people within our eco-system by giving them the very best and very highest [performance quality]. So the net result of those thoughts was PlayStation 4 Pro – and, by and large, a graphical approach to game improvement.”

This is who PS5 Pro is aimed at - though I don't know if they succeeded with this mid-gen refresh, given that PS4 Pro offered much, much better bang for the buck than PS5 Pro.

Games are cheaper on PC.
Online is free on PC.
There are free games on PC.
PC has better graphics.
PC has PS5 games.

Where is the advantage of a PS5 Pro?

Consoles are easier than PCs to use daily and to maintain.  You are also forgetting many people have built up a library of ps4/ps5 games.  

Maintain? What kind of maintenance do you require on a PC that you don't require on a console?

Because consoles need firmware updates, consoles need dust cleaned out, consoles need software patched and more.
They are a PC, just in a custom case with a semi-custom OS... And as such, require all the same "maintenance" as a PC.

Might have been true in the Nintendo 64 era where consoles were easier... But that simply just isn't the case anymore.
Many of my PC's seem to last longer than a console generation as well with minimal work to them... Lost count of how many years I have had this Windows install, even with a few changes of hardware throw in for good measure.

He's not lazy or a fanboy, he just doesn't want to deal with PC maintenance and isn't willing to move on from his PS library of games he's already played, which are almost all available on PC if he really wants to play them. I see, very different.

You know, it's not a crime to buy something and admit you don't have a good reason for doing so. Some people might say that's a sign of real maturity. Wasting people's time with these petty and semantical arguments to justify your spending habits, is usually a sign of something else.

I don't care if people want to buy a PS5 Pro, but they could at least stop lying to others and themselves.

Drivers.  I've had issues with a few games here and there.  

I prefer PC but I think it is wrong to push my opinion on others.  Getting a PC up and running requires more than a console.  Recently I had to deal with Intel over voltage and had to update BIOS.  Many don't want to deal with it.  

Edit

There are also devastating poor ports.  Hogwarts on PC was unplayable for 6 months.  Crashed every 5 minutes.

Consoles are easier, that is just a fact.  

I've tried to convince a friend of mine, who pretty much falls into "money is no object" category when it comes to home entertainment, to switch to PC gaming for quite a while now - he just flat out refuses to move away from PS due to "convenience and physical media". I guess those sort of folks are Sony's potential customers for PS5 Pro (though he has no interest in it, so far).

The biggest ones you'll primarily get to make the switch to PC will be the multiplayer diehards. When I first got married, my brother in laws and their friends were playing Fortnite on PS4. I wasn't a fan of the game, but I didn't want to ignore their invites to play the game. They already loved my PC because of the lighting I had on it. One time they came to visit and wanted to see what Fortnite was like on my PC. Other than the immediate notice of a higher framerate and fidelity, they noticed there were no shadows. I told them I turned that setting off because there were always players hiding under a tree or something and the shadows were making it harder to see them.

This little tidbit blew their minds because that was an issue they always experienced, and you obviously couldn't adjust such settings on console. So over the course of the next year and a half, both of them, and about 8 of their friends all sold their PS4s to build their own PCs just to technically gimp their actual experience

That led to other MP games they love to play like CoD and Apex Legends where they were intentionally making their games look worse to give them advantages. And with account based cross-saves, of course none of them lost anything switching from console to PC. So you're more likely to get a MP gamer to make the switch moreso than a traditional single player gamer.