Personally I think that the right business decision is to let it die. Not necessarily pull all support (keep fixing bugs and maybe do some cheap seasonal stuff) but don't try to revamp it because there's no way that's going to work. Final Fantasy XIV's revamp worked because it was Final Fantasy and the sequel to the still popular Final Fantasy XI.
Basically no other revamps have worked and certainly not this late in a game's cycle.
You can't relaunch a game once it falls out of gamer consciousness. If it has problems at launch but retains a core playerbase then you can fix it and get momentum and get it back on track, but not two years later. Who's going to buy it again? Who's going to buy it for the first time? You can make it F2P (and it already kind of is via EA's sub service) but then the only way to monetize it is through aggressive microtransactions and that gets in the way of fixing it.
They arguably have a moral obligation to make good on all their promises, but even if they did that the vast majority of people who relied on those promises won't go back and play, so it would be pointless.
The time to fix Anthem was in 2019. In 2021 with new consoles it's time to move on.
For similar reasons I don't think Avengers can be fixed, but at least that has the big shiny license, is more recent, and will have a natural soft relaunch with the XBSXS and PS5 versions.