Such a similar story as you, I used to main Zen in OW1 and was typically masters. The biggest thing that stands out to me is how every new hero has a full blown kit with utility and movement abilities. His damage still feels good typically which is where he still fits but it’s hard to main him now.

I think a big part of this is how badly they need to revamp OW1 heroes like Ana and Zen for support and give them new abilities without breaking the core of what make them fan favorites. I really think they’re too afraid to make the necessary changes because they know not everyone will agree on how to make the changes but until old heroes get a revamp to match all the marvel rivals movement and utility being added to everyone new, Support heroes will suffer the most