I think one thing that could explain it is that some of the big tech companies might have been big customers of theirs, and now they have alternatives that, according to recent news, their employees are being pushed to use instead. Some of those reports mentioned internal usage getting cut in half. If this is true, it doesn't necessarily mean their growth has stalled.
Discussed here a few weeks ago: https://news.ycombinator.com/item?id=49997161