Earlier quoted context omitted.
So I guess the question is what made KaiOS able to succeed instead of fail if we're saying the problems FirefoxOS faced weren't execution? Was it simply different timing and now more operators are willing to partner?
The GP is mostly wrong. What killed FxOS in the market is the lack of official support for one extremely popular messaging application starting by W. Then Mozilla's leadership didn't have the patience to wait for the right opportunity.
I.e. if you've got something to claim as the reason it can't also apply to KaiOS unless there was something KaiOS did right that Mozilla didn't.