How can Ranked Solo Q consist of 3, 4, or 5 man groups? My problem with it..

I do not understand calling our Rank system Ranked Solo Q if we are going to have 3, 4, or 5 man groups. I do not care about the toxicity of the groups because I will just mute them. I do not care about being more social with my league friends because all of mine are in Silver anyways so I can't duo. My problem is HOW THE FUCK IS IT FAIR THAT I GRINDED TO DIAMOND BY MYSELF AND NOW SOME GROUP OF GUYS CAN JUST GRIND AS A TEAM AND HAVE A WAAAAAYYYY EASIER TIME GETTING TO DIAMOND THAN I EVER DID?????? Also, it is called RANKED SOLO Q for a reason. Atleast make it where the SOLO Q players get more LP than the GROUP Q players. That is only fair.