Ok first of all, this is my opinion but I think this really is the case.
So. I won't deny that more players play blind pick over draft but if there's like 2/5 of the player base (or a bit less idk) whose main mode is draft, you just can't force them to go play the overly toxic blind pick or more serious ranked. Here's the things what happens because of this:
1. Some players who played draft pick before will quit the game. No I'm not even kidding. This might be me if there's no change in a while.
2. Part of the draft pickers move to flex queue and some treat it like normal draft which makes the queue much more difficult to the ones who actually play it for the rank itself.
3. Portion of the drafters go play blind pick. Most of them probably unpleased by this, increasing toxicity.
4. People can't play normal games (apart from the hated blind pick) with any amount/any skill level pre-mades. Sure it might make the game more fair since it makes the skill gap between players smaller. But you're pretty much killing the social aspect of the game.
That's the consequenses I can think of right now. All in all, removing the draft pick has more cons than pros honestly.
Oh and even if Riot's going to "merge" draft aspects to blind pick, we still can't counter pick. The 10 bans might help this a bit but you're still going to get some of the most annoying champions stomping you.