They're cheaper on PC. 
In all seriousness, it would benefit you a lot more because of the discounted prices alone. PC game prices are often discounted right at release or go on sale much faster. I dunno; I mean, nothing is stopping you from keeping your PS4 and then getting new games on PC if you wanted to try that route. I definitely prefer to get digital games on there over consoles since I don't have to be anywhere near as concerned on whether or not the older games will work or be supported on new hardware, too.
I mean, I get what you're saying... and I agree for the most part (even though we've literally had this conversation countless times for years and years 
)... There would need to be some serious QOL adjustments made to how I game; PC location (my work location basically),and/or running cables to my big TV in the living room... I absolutely can not game at a desk on a monitor. I do too much work at one on a daily basis... I need to lounge when I game.. no question. But I can't move my work PC over there... unless I'm going for a complete new build to invest in... I can't justify that purchase at a one time price (or even monthly payments), all the while, still needing a 4K display... On the Sony route though, I'm willing to take my chance that they won't back out of some form of BC moving forward.. Any PS1-3 game I would consider playing again anyway, I can find the game for free on the information super hwy and play on an emu with better settings than a standard BC would allow, so... I dunno. I don't want to sound like a fanboy, or be packed full of excuses (which I technically am), but there's a lot of gray area that stands out to me still.
TL;DR - I have a lot to consider if going that route...
I know we've talked about this so many times before, yeah, lol.
I just think with you being 100% digital and liking to go back and play older stuff from 1-2 generations ago, PC makes more sense. You could consolidate everything you use into just one machine for games, emulation, streaming, etc. It would be a big change, but you'd be free of being "locked" into the Sony ecosystem and although the hardware you get might cost more depending on what you go with (if you got another PC), it would end up saving you money in the long run due to lower game prices, free games (like actual FREE games from Epic and the like with no sub required), and no subscriptions needed to play games online or get 'Plus' crap.
tbf Steam sales are way overrated at this point compared to PSN/XBL and even physical discounts. Mabye it gets to the bottom a little quicker, but if I'm not day1-ing, then I don't care if it takes 1 year or 1 year and a half. There's more opportunity to get free shit on PC, but then again, I don't think I really ever touched any of the stuff that gets thrown at me.
The difference is that you're not just locked into Steam for games and can also buy Steam or other storefront codes from other sellers. Green Man Gaming might have a good deal on something that Steam doesn't have on sale, for instance.
Also unless you're an insane person that wants to blow money out your asshole daily to the tech lords like Bork: You don't need a 4K monitor. FFS, a 1080p monitor will do you fine for work and gaming for a good long while.
My monitor is 2560x1080, bruh.
He's talking about using a TV anyway and you can get a decent 4K set cheap enough.
