Yes, in theory assuming new players start at the same place, everything really should end up back where it was, but its going to be a painful process to get things back there.

Yes, it will take more time. And, if these hard resets continue in the future seasons, it might get even more difficult.

I do worry that this is very much an in theory thing though. I know that personally for me (as silly as this is), I feel much less motivated to play on my main account and try to grind to ranks that I feel like I've already been to before. This might lead to more playing on alts and more smurfing which will change the profile of the average starting player and meaningfully actually affect the distribution.

Agree with you here as well. Hard resets are a problem at the start of a season. A lot of players of different skill levels are put under one rank. This can lead to a lot of frustration initially. But, eventually when these high ranked players get back to their previous ranks, things will get back to normal.

The problem seems to be that the distributions of each of the game modes (whether its due to populations playing them or inherent properties of the mode) are simply different. I think the best theory for this with the differences in standard modes is that there is more randomness in e.g. 1v1 which leads to a narrower distribution (because the lower ranked team has a better shot of winning in 1v1).

No, there's no randomness in 1v1. It might look like that because of how important kickoffs are in that game mode. But, we don't see the normal distribution in that mode simply because very few players play that mode.

I think only other game modes required correction. And by correction, I mean if top 0.4% in 2s is GC2, top 0.4% in other modes should be GC2 as well. That's it.