The only reason to make something actually impossible is to prevent "Camel is a horse designed by AI" situation I presume, othewise limits goes against the game's whole idea. Physical possibility is crusial, no argue with that,
but why we forbidden to have sonars and smokes on large ships for example?
I'm strongly disagree with "it may be better to make something actually impossible in the game, rather than explain to the player why it was practically impossible" - it's simpler, yes, but not better in any sense. "Yeah, the designer kinda there, but since we consider players unable to think and learn, you can't actually do much with it. Please enjoy the game which treats you like ignorant moron."
If player with zero knowledge skips tutorials and ignores designer warnings he'll learn the hard way, but please don't rob people the possibility to experiment (or just have some stupid fun with meme ships).