IMHO the biggest (and the only?) problem is vendor lock-in.
Does anyone use this? I remember when it came out it. It promised a lot. Reading the first paragraph of this article seems to indicate it’s not doing well.
Not that many users right now, around 100 actively using it, and a handful of people signing up each day. It’s fair to say we haven’t yet made it amazing for people to use (in startup terms, we haven’t got product-market fit). Working on that at the moment, hence the roadmap.