SC has died because it is a 1v1 game with a high learning curve which couldnt court casual gamers in part because of Blizzard's pay-to-play and in part because 1v1 games are just less appealing to play with friends.
I think you nailed it, even if it is more toxic (sometimes) because of the Team, but for most People its way cooler to Play with friends and on top of that.. you can play it pretty hardcore/competive.
Honestly, my most issue is: i'm tryhard/timewaster. To push Starcraft 2 in 1v1 (Dia,Master,Grandmaster) it would destroy my life. Thats why i dont play it. Even the Nova Missions, im kinda hooked and i want to play it but only Brutal and that takes times too. (Well i have a long list of Games i want to Play).
Watching... Well No.
I have no reason to watch streams of progamers, if i dont play.(you dont learn and you dont need to learn)
Big Events... yes, but somehow im an old Guy (older than Day9 lul) and i have so many memorys of old Programmers i liked. But they dont play anymore... thats why i have no connection point or its hard for me to watch games, without knowing the pros, And is it only me, or is the scene missing some charming pro player?
No, doesnt play and doesnt watch. Recently, i compared viewer numbers on Twitch and Hearthstone was quite up there, Kripp was streaming with 50k Viewers, cant remember a SC2 Event with such numbers. A German LP Streamer has most of the time 10k-20k Viewers, i think you need just the right People at the Game.... why did i start watching SC2 Streams? Because of the People.
Artosis is still fine to watch, someother aswell but something on Pro scene is missing..
Sadly i have no Solution to it, i dont think its just be done by a GameFix.