Publishers seem to have it in their proverbial heads that whenever they decide to re-release a game with a little more “shininess” to it, they have to get rid of all the old versions so people don’t get “confused” and buy the older version which generally works fine, or at least is in a state where people know just how to get it working fine, and which also sells cheaper than the upcoming version, so of course this is about charging more for the same thing once again. There’s the insistence that this new version is the “definitive” way to play the game, but then it turns out it’s even buggier or just worse than the previous iteration for whatever reason, maybe due to that added “shininess”, much like the named “definitive” trilogy of the 3D Grand Theft Auto games ended up being.
The latest game I’ve heard this happening with is Yakuza 0, a game that could be gotten pretty cheap on a sale and runs fine on older systems, now getting its “director’s cut” with some added cutscenes and a couple other things apparently, which means they apparently have to remove the original version now. At least they’re offering a “loyalty discount” for a limited time on Steam, which a number of publishers just don’t do at all, but this still seems unnecessary to totally delist the old version. Not to mention the older version in this case has several merits, including being a top-selling great entry point to this whole series which has since been renamed outside of Japan closer to its Japanese name as Like a Dragon, since it doesn’t insist on knowing previous entries to enjoy, leading to the series really blowing up in popularity and re-earning the privilege to be dubbed in newer entries. This is on top of the previously mentioned cheap accessibility.
I’ve seen cases where getting this shiny new version also grants access to the older version, like with whatever happened with the Blade Runner game on GOG. That game’s attempted remaster was pretty broken to the point where it goes on a high discount, which turns out is just an even cheaper way to get the included more functional original version that’s been fixed up to run on modern systems properly, which itself hasn’t been delisted either and can be bought separately for less of a discount. So that’s more of an unusual case, but I’ve seen it happen with other games that did remove the older version from sale, just changing it into a pack-in bonus for getting the new version.
In terms of generosity, sometimes it goes the other way around, where having the old version grants access to the remastered one, like with Skyrim and Bioshock and Borderlands. Other times, and I think more often these days, it’s a paid upgrade, like with the above mentioned Yakuza 0 as well as a number of PS4 games that got redone a bit more than a basic port for PS5. And sometimes it’s just a full price new purchase, no “loyalty discount”, despite being all on the same platform or console family.
Long story short, publishers wanting to be like how George Lucas is with Star Wars, where any time those movies hit a milestone or become available in another format a bunch of stuff randomly changes, isn’t a great business model. For owners of the previous versions, are the “upgrades” worth it? For anyone wanting to get the game for the first time, should they grab the old version while it’s still cheap and available or wait a while longer for the new version to be discounted not quite as much as the old one was?
This works a bit differently for when games that actually aren’t available through official channels anymore get redone, like when PS2 or GameCube or Wii games get remastered or expanded upon, things that can only be picked up secondhand at this point for whatever price they set, outside of resorting to just finding a copy online to download which is easier for some cases than others. In those cases the renewed official availability is more welcomed, even if what’s added or changed about it might not be the most appealing to some if not most, leading to purists seeking out the “untouched originals” or something like that. Of course, emulation has only gotten better over time for a lot of systems, just in case actual hardware and hard copies are out of reach for those interested in history. Games preservation isn’t just a made-up excuse for piracy after all.