Zaretskii's stance is weird. If you are going to run out of people who can work on the core of the editor's source code, then the editor will die. So the lack of ability to work on the code is the real problem. This is probably because it has accreted way too much complexity at this point, and way too many hacks. Shedding some of those hacks is a very good idea.

If you wanted to keep it the old way, and depend on the nuances of how an allocator stores memory, then ship your own allocator. Video game people do this as a matter of course; it's not a big deal.