It's not the same issue, but it kind of dovetails into the argument some people are having on this forum over whether games that have a centralized, online component should remain playable when the publisher shuts down the servers.
Like, if you play the game, and there's only a single provider of the server environment, you don't have an option to play in the "older" environment, even if most of the playerbase wants to play in the older environment.
My own approach has generally just been to avoid games with an online component -- in my eyes, they just have too many issues today to be worth playing.
I don't know how common the Escape from Tarkov situation is, but let me give another potential issue. Let's say that there is an online game that has a significant playerbase, but doesn't have a subscription fee. The game vendor isn't making revenue off the thing after the initial purchase. They do have a reputational benefit of providing service, but aside from that, they aren't really getting anything. And when you consider that game developers and to a lesser extent publishers don't always have fantastic longevity...well, maintaining your reputation beyond the death of your company won't buy much. And even if they do go under, if someone else buys their assets, they can do what they want with them. Like, if there's a clever way to buy up a collection of IP rights from dead game publishers and make money from them, I expect that some enterprising person will probably show up and do so. The publisher may care about their reputation, but that doesn't mean that whoever buys their assets does.
One thing they could do is extract information about the players from their computers, see what value they can extract from that information. The cell-radio-connected-automobile-company route.
I know that something like this happened with Oxygen Not Included, a game that I rather like. Klei Entertainment, a small Canadian publisher, put out a really neat sandbox game. They then had a majority stake in the company acquired by Tencent. My understanding is that Tencent updated the game, said to players "if you let us log and data-mine you, we'll give you the option for new wallpapers and character clothing". And at least in that case, they're still providing players with the option to opt out of the data-mining if they forego the perks...I'm not sure how many companies are just doing it and not mentioning it.
I would imagine that it might be common with games where I'm not looking at what's happening beneath the covers. It's not like there's a lot of visibility into what a game is doing. One reason that I'd like Steam to have games be required to indicate whether they require network access to function from the get-go. Pinball FX, for example, has required network access, though the genre really doesn't require it, and has no way to opt out of those network services. I'd probably not have purchased it if I knew that prior to my purchase, but it's not clearly indicated at purchase time.
Even better would be having games indicate whether they require network access or unrestricted filesystem access at purchase time, and if they don't, have Steam run them in an isolated jail with it off. That's not just publishers, but...games are written on a budget and tight timeframe, and aren't always the most-secure things. If I break into the game servers run by some company, how hardened is the client software used by players against that being compromised? Suddenly, breaking into any of a whole lot of computer systems out there can compromise my computer.
Anyway, aside from the data-mining, another issue could be just putting ads in or something. I mean, it's not like the player got a contract from those companies saying "you get unlimited ad-free service forever". They get some form of service for some period of time.
If they're paying for that service -- the World of Warcraft model -- then the game's publisher has a great incentive not to dick that revenue stream up. But it's pretty common for it to be the case that they aren't.
Steam currently lets a player "downgrade" to an older version of a game. That's not -- as far as I'm aware -- an advertised feature. It's not incredibly-accessible in the UI, and I suspect that few people use it, but it does work. It can be useful for if an update breaks a game in a particular environment.
But that doesn't work if all versions of the game that have been pushed out depend on a server that no longer exists.
And don't get me wrong -- having ads might be desirable. Maybe it's possible for a game to live on, funded by ads, past the point when a publisher could have paid for updates and servers and such. And maybe some people just don't mind their data being extracted and mined. I'm not saying that all free-to-play-but-the-vendor-is-making-money-somehow games need to be killed. But I'd like it to be up-front at purchase time whether one is going down that route, and what it involves.