One of the first things I did early on in Overwatch, back in 2016 was just sit in the Practice Range for about 3 hours and learn what all of the heroes actually did.
This game has a huge learning curve and that’s before you even begin to learn proper gamesense.
It totally makes sense that they’ve identified this as an issue. I have no idea if locking people to a subset of heroes is the best solution, but I know they’ve done a ton of user research and I’m guessing this is one of the things they tested and found to work.
I like that restrictions are lifted when people group up - it encourages people to form friendships and group early on. Thats a nice touch.
I hate that buying the Watchpoint Pack lifts the restrictions instantly. Dedicated smurfs are just going to do that instead, defeating the purpose as an anti-smurf measure entirely.