Blizzard hasn't stopped trying to improve the game itself. However the development team has become smaller over the years.
There are no events for people to participate.
Even if there are events, the money prize pool is crap. 5-10 grand in america for first place? I bet streamers make more money in a month compared to that. The prizepool should be like at least 3 months or more of pay.
Sc2 online tournaments are dull. It's the same 3 round tournament, never a mix. i wish there would be a massive tournament at the end of every season, especially like 5 round or even group stage online tournaments, without third party.
The game itself is extremely demanding, and there is little reward. Other games have a market, sc2 doesn't. people bet, sc2 you can't or that I dont know about.
The community is dying, and blizzard isn't caring about it. Blizzard is still trying to milk sc2 probably due to sales reason, hence you see DLCs being released. People only bought sc2 for the storyline, but after that no more. You see so many people switch from sc2 to other games, because there is more money involved.
MC (pro protoss player) he also said that he's in financial trouble, because he has the skill to be great player, but there is no more money in sc2 tournaments. If you say that there are money and I'm wrong, well I meant that there are far fewer tournaments existing than compared to 2009-2012. That's what I mean by money. SC2 used to have an audience like CSGO,Dota2, LoL, but that disappeared because blizzard and the community are divided. Blizzard no longer cares about the community. It's dead. Sc2 is no longer a career for gaming in many countries, including korea. sc2 pros usually retired by 28-29. dota2 pros continue past 30. csgo players play past 30, LoL players... well Not sure about that, since it's quite new compared to other games. The typical streamer on sc2 has about 100 at most... Most people can't survive on that income.
Dragon (former pro), I watch his stream from time to time. his viewership went from 2011 (roughly 2000-4000 viewers) to 2016 (roughly 50 viewers, on a great day). He switched from sc2 to LoL due to viewership troubles.
Blizzard seems to sit high on their high horse in starcraft2, because blizzard is delusional. They are ignorant. Day9, Husky, biscuit and many other people tried to stabilize the community, but blizzard did their own thing, as you saw in the video. Blizzard is money hungry, they are running without a fan base. Hence, that's why they merged with Activision. Blizzard didn't need Activision in 2012. Blizzard is going to die, so enjoy it while it lasts. Battle.net is dying already, as Blizzard already disowned it. Sign of Blizzard's path changing already. Their focus is Overwatch, Hearthstone, and WoW.
In order for SC2 to be resurrected. Blizzard must make massive changes, which I doubt because they already have 3 games to focus. More games = less resources.
Blizzard gotta change online tournament, hosted by blizzard. that 3 round thing is annoying. it's the same no matter what. more variety is needed.
Other thing is that player skill difference must be minimized. I am gold but playing against diamond. that is seriously something wrong. In 2012, that is unheard of. People are quite inactive in their ladders. I wish there was a rule that in order to maintain ladder rank, players must be active no matter what, upto X number of days, something like Grand Master. Otherwise, you just have bunch of ladder players all inactive.
Also, no ranked players may play against another player higher than their rank by 10-20 places. Like Gold 50 may play against upto Gold 40-60, not Gold 1-10.
Sc2 also needs to eliminate number of servers. Blizzard needs have more versatility when it comes to server accessibility. There needs to be more incentive to play sc2. in csgo, we have new skins, level up, prestige. dota2 has trophies, stats, career stats, etc. starcraft2 has... max level? new skins on achievements, but that no longer works when you can't play against equal opponents?