This argument could also be used to replace Jungle Cruise, which actually fits your concerns better than GMR. The boat system is very outdated, the story is laughable 1960s cornball dad jokes, it has a huge plot of very valuable land in the most popular park and its completely reliant on cast members.
I'd fully support killing of Jungle Cruise for a better use of the land, presuming something of the order of Pandora/FoP. And give up PotC for Shanghai's version. And the current coaster in Space Mountain for a much better one with a smoother ride and better FX. And IaSW for a much better updated one (preferably in Epcot). And Speedway for electric TRON racers (or RC Racers in TSL). I would have been totally on board with TGMR having most of its scenes updated and MMRR going elsewhere, as long as TGMR was indeed updated.
Many of these attractions are noted for being the worst version of their cloned siblings or terribly outdated or terribly maintained, and yet, even with that acknowledgment, people throw their bodies in front of the wrecking ball because they're preserving their nostalgia, not a good experience for the next generation.
Frankly, its selfish.