Elops only responsibility is for the Microsoft stock he holds. Stupid or damaging long term decisions can always be rationalised with short-sighted gains. And nobody can blame him for acting in his own interest.
Who ever hired him already knew that he'd elop:e with Microsoft. We've got them to thank for this.
The fact he's there, means a majority of the board is already infected with the same goals.

In the end, the only useful purpose of a huge corporation is to amass wealth for a few individuals, not create useful products. I hope we've all learned this now.

If we want an open phone platform, we need to look for smaller companies, ones that can resist the temptation of the huge profits gained by an app-store on a locked down device and just focus on their core business.