I wonder how many of these companies burned cash to acquire customers, thinking they could jack up rates to improve profit. At the first sign of this, people jumped ship. Also any significantly large client will migrate to a lower layer to save cost. This means your business is effectively locked into SMB, because the enterprise market is just not there.
Wasn't it obvious about 10 years ago when Docker started booming in popularity that PaaS was on it's way out? The only space left is K[38]S offerings at different price points and whatever neat add-ons makes sense (like a free registry)