Anyone who complains about an end-game transition is being stupid.
Part One: Inevitability
In any game with any sort of progress you're going to have a tendency toward an end-game. Either all measured progress stops or it changes in form. This is not necessarily by the design of the developers.
Consider a game such as Banished or Don't Starve. The initial game is a struggle to not die horribly. You try to get sustained heat or light and food. This means chopping trees, foraging, hunting, and hitting rocks. Eventually you've chopped so many trees, foraged and hunted, and hit so many rocks that you're not likely to die a horrible death at any given moment. You've stabilized your situation. Your people have shelter, they make enough babies that enough will grow up to make babies to sustain the baby-making cycle, and you generate enough surplus food that even if the houses are filled with babies you won't suffer from baby-induced starvation. Alternatively, you have enough trees and grass around to keep catching rabbits, your rock-based structures are set up, and you have enough non-renewable materials to last a very long time.
Now you're in the end-game. In a game that doesn't have one, but it does anyway.
Unless you do something actively stupid, such as switching all your farmers to the quarry, or going in caves naked with no torches, you're unlikely to die any time soon. With the basics taken care of you can focus even more on exploration and expansion. Now you can build another Market Economic Zone branching off from your original Capital Economic Zone, and eventually fill the entire map with housing and farms, altering their design to ensure the maximum number of non-starving people. The survival game has become a spreadsheet-based optimization game.
Part Two: Your Counter-Argument to Part One is Stupid
Part Three: By Which I Mean, Adding New Problems Isn't a Good Solution
Banished could figure out new problems to throw at you. Maybe you think you're such hot shit for having stone houses and locally-sourced plum brandy from a sustainable orchard. Well what about when the developer patches in alcoholism and makes the dead rise up and eat all your peppers? Now you have to divert your precious iron supply to swords rather than tools and your physician has to do something other than wait around for dirty nomads with their weird foreigner diseases. Bam, challenge returned! In a totally artificial and annoying manner.
At least for me, and my opinion is the best one, these sorts of games are about the struggle toward that stable point. You figure out the immediate crises (food), deal with those, work on the near-term problems (housing), figure those out, and amidst all of that work toward dealing with long-term issues such as not running out of tools next year. With that generally worked out, you create some guarantees for the future, such as a trading post, so that you can supplement your theoretically-limited supply of stone, iron, and coal, with pepper trades. Now you can survive forever. That's kinda neat.
If the game then added in a new type of problem, then I'd probably just get mad at it. I just built this town hall and now you're telling me I need to beautify the streets or get voted out? I'm the incorporeal dictator!
The game could add a decay mechanic, but how are you going to tune it? If the decay uses resources that can be unlimited, such as trees or rabbit corpses, then it's essentially just another long-term sustainability mechanic. I'll set up a few more traps and declare victory.
If the decay uses resources that aren't unlimited, then the game is essentially saying "this game is about survival and I am going to kill you, guaranteed." I don't mind the inevitability of death in a game, but can I at least go out with a bang rather than a whimper? Surely it is more fun to see that the end is coming and bravely stand against the onslaught of violent death than to mine the last rock and know that the next baby born will die shivering in the cold. Maybe that's just human nature, to want to face something that we can punch, such as Russians, rather than resource depletion.
Part Four: I Stop Writing Soon
A truly pure survival game sounds stupid to me. Survival is a limited thing. It is either a pointless struggle against the inevitable or a pointless struggle. I like it when a game has survival that can be overcome, and when it is, something can be built. In Banished I didn't just survive a winter, I also built a town that can survive many winters. Perhaps that is also a bit of human nature: while animals survive, humans build and develop. Even if the rules of the universe still call for survival, it is no longer at the front of our minds because we've built to insulate ourselves from it, with markets, laws, and literal insulation.
So I say to you, if you think "the end-game transition" is both bad and preventable, then you, sir or madam or other old-timey polite moniker for your identity, are an opponent of all human progress, and probably alien progress as well.