i feel that Dynamic isn't really SoloQ and cant be defined as such.
Your friend queing up with 4 Godlike Smurfs would result in a Instant Plat ranking.
Your unskilled friends could pick Annie + annivia mid etc and just do very little aka AFK, While the Jungler Babysits that lane.
Mid/late game your Smurf buddies top/Bot/jungle just rain hell on the enemy team and gg.
Riot has destroyed EloBoosters by implementing a Eloboosting que that allows them to legally boost anyone they like.
Now all you need to do is offer ''beginners'' a Spot as support/Mid anivia on your team.
and they get boosted to atleast plat.
League of legends already had Ranked 5's, i think dynamic que is just a Overkill.
Because DuoQ was already a significant risk, and everyone knew that if you could que as 3 players you can control all of the map regardless of who you face.
So SoloQ will eventually become Ranked teams.
but on the plus side, more ranked teams will exist and hence Compete on a higher level, many players, do not play ranked teams because they are not used to it, so now we will have more ''teams'' competition and being on a team will be very important.
I think that Players that QUE alone should receive more LP and other things, because they deserve it.
Also people that Que on dynamic should receive far less IP, so that they need more wins to compensate for their advantages.
Diamond SoloQ player > Diamond dynamic player
in terms of effort and challenge.