I have only worked in two engines, being Unity and GameMaker Studio
GameMaker is fine for what it is. If you have never known what it is like to develop a game before, this is not a bad place to begin. You can easily draw sprites, set objects, and work through camera controls with minimal issues. But it is a pretty limited engine in the grand scheme of things, and only a handful of games ever made for it have been any good. Undertale is just about the best game you will ever see out of the GameMaker engine. I understand there is a GameMaker 2 that is a lot better, but I havent used it.
Unity is a much better engine to use once you understand the basics of how a game engine functions. Unity was made to be just that, a super simple game engine that also gives developers a slew of customization options. But like GameMaker although to a lesser extent, it can be hard to hide the fact that games were made in Unity without a really skilled team. I may just be speaking from having a few years of Unity experience now, but when I can easily tell that a game was made in Unity, it makes it feel cheap, and this is usually due to simplified art styles. I'll chalk it up to Unity being easy to learn, easy to master, but difficult to perfect.