Game in-comp locks up and application dies on hero selection screen

I’ve been having this problem exclusively in competitive mode, with maybe one occurrence in qp. Everything goes fine until I get to the hero select screen and pick a hero, whereupon the game will freeze and stay on a frame. The in-game cursor will still work, but otherwise everything remains unresponsive unless I hit crtl+alt+del and start up task manager, which forces the overwatch off the screen.
If I go back into the game, all that I get is a completely black screen with the in-game cursor and no kind of other response from the game, not even sound, so I doubt that this is purely a rendering issue. This has happened both before and after I defragmented my HDD, so I doubt that it has anything to do with read times.
I do not want my SR to suffer any longer because of this. Barely climbing out of bronze a year ago was a kind of labour that made me throw the game away for over a year and was difficult enough on my nerves. Dropping back into bronze with suspensions and penalties for a dysfunctional digital product that I had paid for and still have a licence for, and which didn’t have this kind of repeated operational lapse a year ago, is a different matter. I did not experience this kind of crash since I bought the game at around the time of its initial release in 2016, so I doubt that my specs should matter, especially given that it is a crash localised to hero selection.

So the question is: do you want to keep a returning player at all, let alone satisfied?

EDIT: I’ll add that I have received a -75% penalty and a long (30m?) ban on competitive, alongside with my endorsement level and SR going down by 1 and 50 respectively.

If you want to keep players you better have an answer for this because hardly anyone will gladly shoulder penalties for dysfunctional games.