3 very crap reasons given there, which were.
1 - Allow solo only players all play with no groups so a good pro team doesn't hammer a bunch of solo strangers. (Which will spread players even thinner and cause much longer matchmaking times!)
2 - Allow the picking of only certain maps, so you only play your favourites. (Leading to certain maps having 0 gamers on them, while others are heavily populated!)
3 - Allow deciding what character gets Loot items and getting Xp and boosts for your favourite character (The point of the game is variety of heroes and you cant always play your favourite characters if someone else picks them first!)

What they really need to fix is this:
1 - Winston's main gun is no better than a water gun unless Mercy is boosting his damage. If Mercy is not willing to do that, then he has little to no impact on the game whatsoever and most heros can stand directly in front of him and gun this "tank" down barely suffering 20% health damage. His weapon needs about a 10% damage boost to make it more viable, but not too far that he ends up wiping out 4 players in a single attack with it!
2 - Fix the Draw maps, Looking at you Anubis and Hanamura, 50% of games end in a draw. What they could do is count the "segments" on the capture dial as points. That way if one team captures a third of the way on the second point, while the other team captures two thirds of the way of the second point, the one that captured the greater percentage wins. Maybe even divide the capture points into 5 rather than thirds so there is more emphasis on trying to hold it for those few valuable seconds to get an extra bit of the dial filled up.
3 - Start doing a Symmetra and begin adding alternative Ultimate powers for other characters. This will refresh the older characters with new features, even adding one new Ultimate to another character can change the strategies of gamers completely after months of using the same strategy, bringing other heros (like Torbjorn) into a more attacking role on more game modes, and will reduce the need to see more and more new heroes added. The changes to Symmettra and giving her both a Teleporter for speeding up getting into the action, while now having a shield generator for the last defence makes her valuable in multiple strategies on most maps now. If you made the Ultimates a Offense and a Defense one it makes the characters dual purpose depending on if your attacking or defending. Torbjorn, for example, could create a flying drone turret that could shadow him, doubling his firepower as he attacks for 20 seconds. Widowmaker could have 10 seconds of Rapid Fire sniper shots, with no power recharge time, Mcree could have a Multi Stun Grenade launcher, where he throws/launches several stun grenades into a large area and everyone within the area is stunned for 2 seconds. Winston could throw out 3 Tesla grenades that lay on a floor constantly firing for 10 seconds like an electric bonfire, blocking a path or damaging groups on control points en-masse.

Blizzard is readying a patch to address the issue that the game is still running in Switch 1 build and just 30 fps.