It was acquired by Samsung, which is notoriously bad at open source. But the reason why it quietly faded into the background wasn't that. It was that Joyent's ex Sun people had an annoying elitism that made them not care about working with the community.
Many/Some of them are now working at https://oxide.computer
I mean when you're that far ahead of the class is it any wonder?
(citation needed)
It was acquired again in 2022 by MNX [1].
[1] https://www.tritondatacenter.com/blog/a-new-chapter-begins-f...