When they made OW2, they replaced OW1 with it. Technically, I think OW2 is just a really big update for OW1. But now there's no way to play the old version that a lot of us liked better. :(
I don't think so, only because most of the 360 games available for back compat on the Series X are already ported to PC, a lot of them can be accessed on PC by way of GamePass, and the rest can be emulated on PC. You cannot currently emulate PS4 or PS5 games and only a handful have been ported to PC so far, so original hardware is the only option for playing PlayStation exclusives. Whether to get a PS4 vs PS5 is debatable imo.
If you're planning to do everything the legal way (i.e. no emulation of games you don't own), don't want to buy discs to rip, and prefer the available Xbox & Xbox 360 games to the PlayStation exclusives, you could get a Series X--but honestly, if you are cool with buying discs and don't care about PlayStation exclusives, getting a 360 would be a significantly cheaper solution than a Series X, especially since there aren't really any console-exclusive Xbox games in the last couple of hardware gens and the 360 had better back compat for OG Xbox games than the current gen Xboxes do. So if you were gonna swap the PS for an Xbox, I'd personally go 360 over Series X.
Idk if it's "bad," exactly, but I don't like it. I liked the meta for the first game way more, I miss the old 6v6 team structure, I don't like the changes made to my favorite characters, and the monetization is really sucky. It felt to me like they took everything that was wrong with the first game, kept it as is, and then took a bunch of the good stuff and made it worse. lol
But that's just my opinion, I know there are def people that like it. I only wish they'd release "Overwatch Classic" or something so that people who prefer OW1 can still play it--ideally with the lootboxes removed and a way to unlock character skins and stuff by playing those characters and progressing, but I'd honestly take just like a snapshot of the last stable release before the OW2 update. It was one of my favorite games and I just really don't like the OW2 updates. 😥
Here is what I believe to be the definitive answer for maxing out your library on 4 inputs:
Gaming PC/Steam Deck - you'll have access to a sprawling library of games from all generations and can even emulate console exclusive games from previous generations. The reason I'm not recommending an Xbox console on this list is because basically every current gen Xbox One (+ X|S) game is already on PC (as are many OG Xbox and most Xbox 360-era games), GamePass is an option if you wanna play some OG Xbox/360 games legally, and emulation can get you any games that aren't available otherwise. Sony is also making many recent PS5 exclusives available on PC now with more to come.
Nintendo Switch - it's got a kick-ass library of exclusives, almost every Wii U game has been ported over (minus like ~8, I think?), they've been remaking/remastering a lot of older games and are reportedly going to go hard on that for the remainder of the Switch's lifespan, and with NSO it has a respectable library of retro Nintendo and Sega Genesis games if you wanna go the legal route.
PS4/PS5 - A PS5 would be ideal for maxing out your possible library size, because it can play any PS4 or PS5 game; however, there also aren't a ton of PS5 exclusives at this point in time, PS5 games are being ported over to PC faster than PS4 exclusives, many recent PS5 games are also on PS4, PS4s are cheaper, and the PS4 can be jailbroken. There's a case to be made for getting a PS4 instead.
Modded PS3 - Especially if you can track down a phat model with hardware back compact support, you can load up a HDD with games and play the entire PS1, PS2, and PS3 libraries.
With these four, you should be able to play essentially any game ever made. You will have...
Official hardware support for:
PlayStation
PlayStation 2
PlayStation 3
PlayStation 4 and/or 5
Nintendo Switch
PC (Astonishingly huge library)
You will have the (paid) option of legal software support for many of the best games from:
NES
SNES
Sega Genesis
Game Boy
Game Boy Color
Game Boy Advance
Nintendo 64
Xbox
Xbox 360
You will have the capability to emulate anything from Atari 2600 through to some Nintendo Switch, including Xbox, Xbox 360, GameCube, Wii, Wii U, arcade classics, and many, many more.
IMO, this is the best way to max out the 4 ports on your TV. You can also get a PS Vita and mod it for PS Vita + PSP games, and a 3DS modded for 3DS and NDS games. They don't need to be plugged into your TV, so they weren't included on my list of 4, but they are both excellent handheld consoles with great libraries.
Dunkey, Let's Game It Out, NakeyJakey, Digital Foundry, and Gameranx are the ones I watch most regularly.
The Architect of Games and Razbuten are fun ones if you like video essays, and Keenengraz is great for finding lots of insane free games to play. ThatGuyGlen has some cool, short docu-style videos on the making of indie games that are really well done.
I'm sure I'm forgetting plenty, but those are some of my favorites, for sure.