Players that are afraid to engage any fights shouldn’t be allowed to play ranked

"They can still play in pub. They can still play with any style they want, just not in ranked, which is all about getting RP by engaging fights."

They can play any style they want in ranked or pubs, that is why the lower ranks exists.  If you want better play get out of those ranks, find teammates that play like you and it will be easier.

I soloQ out of those ranks with no issue so anyone can do it.

Better mindset to playing ranked is stop trying to control the things you can't and just worry about how to improve your own game, if you plan to soloQ.