Thank you for giving some detailed reasons. I can't address all individually at this point in time, but I still want to give some clarifications and explanations.
There seems to be some misunderstandings how the division system works. It is not used for matchmaking at all. Matchmaking happens based on rating.
The leage system does take opponnent's ratings into account, just indirectly. Every division has a rating range associated with it and people get placed accordingly. Now if it were to happen that the rating increased but not your winrate (for example because you got matched with higher rated players on average), then at some point your rating is higher than the range of the division you are in. You will then get extra points for each win until you are promoted to the division you are supposed to be in. Similar for the case that your rating drops. This way divisions always correlate with a certain rating range, so they can be used as a rough skill estimate.
the problem with trueskill rating
You gaining 12 points after a win doesn't mean that your skill improved by 12 points.
Your level of play varies from day to day. It depends on how well you slept, how exhausted you are from the day, what your current mood is, etc. When play against someone with 1120 rating that doesn't necessarily mean that that person is a harder opponent for you than the 1070 rated guy in the next game, even though he has higher rating.
1120 is just on average better than 1070. For a single game they are too close to make a definite call. In lower ratings this is exacerbated by the fact that people might be good at some aspects of the game (air, small micro maps) and bad at others. So depending on the map they might vastly over- or underperform relative to their rating.
Trueskill is still accurate on average but frequently people read too much into it, because they don't understand the limitations of the system.
This is no surprise because we don't even show rating as what it is. In reality it is always a gaussian distribution. Instead of displaying rating as a single number it would be closer to reality to show it as a range like 1120-1610. And I am not exagerating the range. This literally the range of established players where it's 99,7% (+- 3 sigma) certain that the real rating is in this interval. The size of this interval should show you that thoughts like "but this player has 40 more rating" are pretty meaningless in reality.
Using the lower end of this range to establish a leaderboard is a completely arbitrary decision but necessary if you want to use rating as a leaderboard because you need comparable numbers. You can't as easily compare different gaussian distributions.
So no, showing rating changes the way we did before is not as beneficial as you think because it carries less information than you think it does.
I hope that I could show with my post that divisions give a good enough estimation of skill while getting rid of the noise that is prone to overinterpretations.
additional examples why we need to hide rating
With the league system we can do adjustments that we can't with just the rating system. For example we can place people lower than they should be on purpose, so will be dragged up by the bonus points simply by playing. That is the enhanced progression FtX is talking about. The downside of this is that the rating spread in a single division increases. Now, it seems that people value it more to have a gauge of skill of players, so I made preparations to disable this soon, so in the future you should only see people of similar rating in a particular division.
We also can adjust things like 1v1 rating being lower for the same skill. We can't easily foresee the consequences of changes to the rating system. On the other hand it is trivially easy and it won't have side-effects to change the rating range that divisions are associated with. This way we can bring different matchmaking queues more in line with each other.
Both these adjustments make it necessary to hide the underlying rating to really make it work