This is getting confusing with all the post disappearing and moving, but thanks for reopening.
Regret, you think of maps as just texture + heightmap. However, maps should not be limited to just that. A map is the world you play in. A world in its own right, with its own specific rules. Rules like: The ships sails in the blue water and not in the green grass. Or like: There is no wind on the moon. Or like: Cheap fusion in speedball.

Or like: This plate is a teleporter. Or like: Here is a city. The rule and the scenery goes together as a consistent whole. If you brutally separate the two, it would be as ugly as a maiming a live puppy then offering it to a child.
To be less theorical, I'll give you an exemple. That map
Palladium I made, if you block the gadget, it's just a flat expanse of terrain, where the texture on the ground do not correspond to anything. I do not want anyone to play it in such condition. I do not want anyone to think I released a flat uniform map with weird paiting on the ground. I do not want anyone to associate my name with what it would be with the gadget blocked. It would not just be "blocking a feature of the map", it would be making unsuspecting people play on an abominably wrecked up form of my design. They'd think I'm an idiot for making such an awful map, while in fact it would just be because YOU had been wrecking MY work, while still presenting YOUR wrecked up version as mine.
So I request that you should not be allowed to ruin my works, or any other mappers work, in such an abominable way. I say it's abominable because you could completly remove the point of map, turn a masterpiece into a dung, while still pretending it's the orginal form since, to the unsuspecting eye, since the file is the same, not re-released, then it must be the orginal, and so the blame for making the bad map would fell on the mapper instead of the host who ticked the option to strip map of half its content.
Also, the point about "play another authost", and "play another map", are not trolling, but valid point. If you do not like a map, you shouldn't be allowed to twist its creator vision into ways he doth not want. Instead you should respect the creator vision, and if it doesn't suit your taste, just step back and go fetch something you like more.
Your point about "what if the map was good without the extra feature" is not valids, because there is no map shortage, so there's no such a case where you desparetly need a modified version of map. Also, if you manage to be civil, you can just ask the map creator if he'd be inclined to fix this and that flaw you noticed, or to make a variant like this but without that. However, that way, it would still be the creator of the world that'll decide where to split, how to modifiy, and so it would be done in a consistent way. Automated programs cannot be trusted to understand how to modify maps in a sensible way, but a map creator, if he agrees to your pov, could modify while still preserving the map coherency. For exemple, again, on my map
Palladium, I made map option to disable the ramp lowering/rising in midgame. But still kept the initial terrain deformation that makes the map what it looks like. How would a raw one-algorithm-fit-all could know precisely which lines to keep and which lines to throw, when they are in the same .lua files? Of course it can't! That is why you should never add a tickbox to strip maps of half their comment.
There, a long post discussing the feature and not refering to meta-discussion about how Regrets ways of arguing are despicable.