It's not the removal of seperate rooms but people with a weak ass mindset (just like you) inside this competitive environment, that´s slowly killing the sparring community.
The point where people don't want competition anymore is when a competitive community dies.

People like Sarah, love her or hate her, are what keeps such communities alive actually. Polarizing people who spark competition and push the meta forward.

There´s also a lot more factors, like the servers getting ****tier or the iDev freeze as well.
Simply adding back seperate sparring rooms wouldn't have much of an impact, there´s much more grave things at fault here that need to be addressed first, in order to "revive" the sparring community.

Grow up and adapt, things change and so did the sparring community