I have seen lots of back and forth on this matter however a lot of the time it feels like its coming from quick play or more casual experiences. I thought I would try to provide some feedback regarding experiences felt in the competitive space.
I am someone who personally prefers collision on regardless of the mode, whether casual or ranked, so keep that in mind when reading this piece. For further context in the current Beta test I am ranked in diamond for the arena mode and the discussions I have had in a lot of games with the other players in the lobby seem to be on the same page. (Obviously small sample size)
I have experienced a few too many times going into melees trades or trying holding a doorway for people to run through me and get a back-smack.
When it comes to playing ranked, this is something that I believe does not add any additional skill to the game and potentially takes away some skill. I am of the opinion in a best of both worlds scenario, for those that are begging for it to remain, no collision should at worst be applicable to team-mates but collision on for enemies.
The complaints about teammates getting in front of shots etc are annoying however it would be less expected in a ranked/competitive environment. Having other team players push points by phasing through you just seems to bring nothing additionally to out-play or play around other than maintain your distance.
For me personally, I would like to see player collision in all modes however, I would compromise to at least have only the enemy have collision enabled.
Other than this nit-pick I am overall enjoying my experience with the game, I am aware of the efforts towards working on changing the battlepass so I see no further need to dogpile on it.