I personally think the mistake was announcing that Blaze was being abandoned (basically this post) when the plan was do decouple and open source it, people are still using and liking Blaze till today and they can use other view layer if they want to.
Back then meteor was blaze, and the community wrote tons of atmosphere packages so naturally a lot of people freaked out. So to write an “emotional” post about not supporting blaze, in my opinion, was the trigger for the FUD in 2015.
Again that’s just my personal read on the situation, I think Meteor has improved tons since then.