It's unlikely habitat upgrades would mitigate criticisms. The Blue World Project was SeaWorld's concept for upgrading their exhibits in San Diego and later other parks, but the activist response was best summed up as "a gilded cage is still a cage", and after the intense activist outcry, the project was approved by the California Coastal Commission under the caveats that breeding would be banned and that no whales could be moved into or out of the park, including rescues. As far as I know, no other orca-holding facilities have attempted to upgrade their facilities since the period of intense scrutiny began.
As for ignoring, it does seem to work actually. SeaWorld has seemed to bounce back pretty well from Blackfish, and, of their ads I've caught on TV or elsewhere, I've noticed they keep the focus well away from the orcas, in fact I don't believe I've seen them in an ad in a few years. As a result, though, the protests that had been occurring outside of the parks from organizations like Empty the Tanks have pretty much fully stopped as well. I will note that in the post-Blackfish period, they ran a PR campaign called SeaWorld Cares to try to address activists, but it never really worked, and only really reinforced those for captivity, it didn't do anything for critics, who accused it of being all lies and PR.