There is a ranking system for smash albeit community based and not an exact science, my grandfather was a regular in a pool hall and everyone knew how they matched up to him because they played there often to. although they dont use algorithms for pool/smash its normally well understood the level of skill you opponent has.
and as i say before people 1-15 have been beaten by bots, i have a friend who has lost to beginner bots and could barly even stay alive in lane against other players her mmr. smurfs will ALWAYS have higher mmr then legit new players and there for will not be matched with them.
as i have said before i own about 5 or 6 accounts and this has ALWAYS been the case without exception. i may get a new player here or there but generally its always smurfs and the new players i do get aren't halve bad (all considering). no ones experience has been ruined at all, they only found out about the smurfs afterwords then complained because it felt unfair only after having it planted in their minds that because the game wasn't stacked in their favor they lost.
This entire thread is complaining about smurfing, the simple fix that is improve your own gameplay. stop complaining that they are better then you and deal with them as is. i've played soloq for my entirety of the time i've spent playing league ( with the exception of this last month where i've had a friend who wants to duo all the time) and i know what its like going up against and being a smurf. neither situation was toxic/harmful to the community. even when i announced i was smurfing people either didnt care or didnt believe.