Games will always be available to play in some form, like rereleases/compilations or emulation. It's just that playing with original hardware as collectors might eventually become problematic except for a select few people with the resources necessary to keep the old hardware running properly, even dealing with original CRT displays which will be needed for lightgun games. I just remember all the various Atari 2600 compilations available throughout the 90's and early 2000's for PC and various consoles.
You're the one who brought up framerates and slowdown, saying Super Castlevania IV had slowdown and Metal Gear Solid 3 only had 20fps. What I remember about those games is that I had fun playing them, I don't care about technical specs as long as I'm having fun. I'm not against all modern games automatically, I just don't feel strongly enough to play most of them.
I don't really feel much interest with most modern games as they all feel generic, probably because the characters are mostly forgettable. No more characters like Pac-Man, Q*Bert, Donkey Kong, Mario, Sonic, King Graham, Guybrush Threepwood, Lara Croft, Crash Bandicoot, Solid Snake, etc. I watched a let's play of The Last of Us and I can't tell you the names of the main characters besides Ellie(ie generic girl). Even if they play well they still feel like cheap knockoffs of better games, the way Socket is a ripoff of Sonic and nobody remembers it. Who's the guy in Dishonored from Bethesda? I played it briefly before selling it off, I just don't care enough about it to feel invested. I do want to play through Alan Wake when I get a chance, it seems interesting from what I've played so far and I can remember the guy's name which is something.
Yes there's a lot of trash on those old consoles. Am I playing Total Recall, Action 52, Rise of the Robots, Bubsy, Shaq Fu, or Sword of Sodan? No, I'm playing the good games from those consoles. The good games were mostly 2D, bright and colourful, mostly upbeat, memorable characters, just fun. I can just pick up and play them without long tutorials to learn the controls. Just look to Rocket Knight Adventures or Aladdin on the Genesis as examples.
I do end up watching Let's Plays of modern games, they're fun enough when someone else is playing through them. I don't have much desire to play those games myself though. Bloodborne isn't my type of gameplay, but I do see that it's a well made game.
It's fine when you're not really invested in any of the games that much. Even those "Achievement Unlocked" pop-ups annoy me for the same reasons.
There is actually a way to turn off those notifications, a lot of these youtube people just forget to turn them off and don't want to bother rerecording footage so they leave that in.
As for the whole rich man's game, it's yes and no. If you're just starting out and have to buy everything from scratch, it is cheaper now compared to how expensive everything was back 20-30 years ago. But we're different as we already have TVs and dozens of consoles with hundreds of games to play, anything new just brings up the question of do I really need to upgrade from what I have already? For the most part, I would say no I don't. It's why I'm sticking with my Samsung Galaxy III smartphone as it's doing what I need it to. And I still don't own a high def TV, maybe I'll upgrade when people are throwing them out for the new 4K TVs everyone will be upgrading to, before whatever replaces them just 10 years later. Don't forget to rebuy your movies too!
Gaming wise just stick to PC games. Everyone basically owns and uses a computer(with or without gaming in mind), and getting a basic one for around $600 new will last around 10 years easily for most needs if not longer. My laptop is almost 10 years old at this point and I can still surf the internet, watch online videos, and can still play most modern games just fine. Maybe not at maximum settings but they still can be played. I remember when buying a new computer in the 90's would be around $3000, while consoles were around $200-$300. There's little price difference now.
It's funny you mentioned PS1 and Dreamcast, back when those consoles were current a large percentage of the users would just be modding the systems and pirating the games for them instead of buying them. Same for the PS2 and Xbox really, the N64 and Gamecube were more difficult to pirate and also sold the worst of their generations. Going further back most people only used to own maybe 10-20 games total for their consoles because of how expensive they were, it's not like people just used to spend more money on video games than they do now, they just bought less. The Dreamcast sucked though so I don't have money wasted on that, I only have some N64 games left as they're complete and I'm hoping to trade them for good games at some point.
There was a time when buying a movie on VHS would cost around $80-$100, now you can buy a new DVD from a bargain bin for under $5 including collections of 50 public domain movies. Just going by inflation rates isn't a great standard for deciding what's affordable, entertainment as a whole is cheap now with a large thanks due to the internet.
Also I tried playing Dishonored for the 360 on a standard CRT. All of the text, menus, and information on screen was illegible. You pretty much do need an HDTV to play anything modern properly.