I don't know about most but many are happy with UAE.
Indeed, so your statement..
Without cheap low end Amiga hardware, there will be fewer and fewer Amiga users and developers wanting high end hardware similar to what they are familiar with. That's game over for the Amiga.
is bogus, because we all, and many more with us, are keeping Amiga alive on UAE. If cool 68k hardware shows up, it is awesome, but emulation works fine too!