Yeah. Also, there is a 3rd type of game you didn’t mention: The kind where you buy the main game and it’s updated, but doesn’t change much, overall. These updates usually just have things like bug fixes and small quality of life improvements. Also, sometimes, these games will be out awhile and will release DLC that expands upon what you originally bought, but isn’t a full sequel, is optional, and doesn’t “take away” the original game you bought.
Honestly, that’s the kind of modern game development I love (when done right). Because it brings both of your other examples together, in a hybrid form. You still get the game you want, but unlike the old days, you can now get some of the bugs and glitches ironed out instead of having to just “deal” with them. And, sometimes, you can even buy extras (DLC expansions) to “tide you over” until a sequel, or another game you like that you’re waiting to release. In my opinion, this is modern game development, at its finest. Again, when done right.
Games of the old days can fall short a bit, in comparison to these “hybrid” games we can now do. Sadly, though, because of the existence of those hybrids, it makes games like Gems bittersweet. Part of you goes: “Great, in this day and age, Gems can, theoretically, live forever.” But, do to wants and needs outside any one players or probably even devs control, that game you started playing in 2016, may not be the same game in 2018, even though it has the same name. And, yeah, that can be good or bad, but either way, like you said, you can’t “go back” like you can in the other examples, and that is the part that saddens me greatly.
You see, my voice on this forum was never to “kill off” this New UI/New Style version of the game, it has a right to exist for those who love it, just like any other game. I just wish I could play the game I fell in love with as well, you know? In a purely, logical, on paper, way of thinking, that sounds fair, in my opinion.