While companies move off Heroku because of the pricing, there's still a huge addressable market there given that the Heroku ecosystem (including all its addons) is much more extensive than other similar services. The OP discusses this (that's what the "magic" is all about). Plenty of folks would be willing to pay the Heroku premium if new features were being actively developed, the addon ecosystem was continuing to expand (and addons were kept up-to-date), and the general reliability of the platform wasn't being questioned.