https://theforeman.org/manuals/3.0/index.html#Releasenotesfor3.0 - "Puppet ENC functionality extracted to foreman_puppet plugin" indicates "By default, this plugin is still installed in 3.0 both on fresh installs and upgrades, but will default to off in future releases."

Meaning that 3.0 isn't breaking and sometime later it is.

https://theforeman.org/manuals/3.1/index.html#Releasenotesfor3.1 contains no mention of this, and this is where we got broken.

I really think that should've been in the 3.1 docs. It took us a while to go backwards and see what we missed in 3.0.