Imagine one second that Blizzard did what gog did directly, re-releasing warcraft2 with nothing changed just making sure it runs on modern computers and making people that already bought the game buy it again for it to be fixed.
Do you think people would think that is ok?
Yes, this is OK. Except one item "buy it again". If you have your historical copy, I think you can play it with DosBox, new ddraw, on old PC whatever you have. From another side, I had no possibility to have a legal version of Warcraft 2 at all. It was crazy situation in my county in 90th and Warcraft 2 was available only like this:
When I wanted to organize an offline tournament it was a trouble that I have no any legal version of the game. The only workaround was CD from e-bay, which cost very much. Now this is not a problem. And I have bought both of GOG versions immediately, to pay Blizzard for my happy hours I had 20 years ago and have now.
And new players had no possibility to get a legal version if they want. Now they have. You can play as it was before GOG release.
Now if yes then what stops them and any company from making you pay your games all over again the next time DirectX or your OS is updated?
I don't pay Blizzard for "updating" my Warcraft 2. I pay only for old game as a whole product.
OK, lets talks about OS. I have found a rare, old but very useful specific hardware. It run under Windows 3.1. I cannot buy Windows 3.1. because it "has no updates" and it is "abandoned". So I cannot use my specific hardware in a legal way. I want to pay money but I cannot. Is it OK?
By the way I had a similar situation ~10 years ago and MS send a response that I'm free to buy any modern OS, but do not install it. Then I can install old OS I need in any way I want, but without using illegal sources (like forbidden torrents or pirate's disks) . And this installation will work for me.
PS In any case I'm happy that anybody who want to BUY old software has possibility to do this.
PPS And one more related to my first post in this topic. I just wanted to point that there is no term "abandonware" for market. We can talk a lot if this game is old or not, if we need it in shop or for free, and so on. But this is just abstract discussion. Just for fun. And it does not make sense for real life now. But any discussion is good, because it can change something in future.