- nginx is "open core", with some useful features in the proprietary version.
- angie (a fork by several core devs) has a CLA, which sounds like a bait and switch waiting to happen and distro's won't package it
- freenginx is at least open source. But who knows if it'll still be around by June.
I had been an Apache user for quite some time, and thought I'd take a look at the (at that point, a few years old) "new" shiny thing. I found that something as simple as LDAP authentication required a payed plugin; a free Apache module has been available for this for ages. That made nginx a non-starter for this particular use case.
I wonder if the fork will accumulate free plugins for things that the old core required payed plugins for, slowly eroding their business case.
Unpaid Open Source developers tend to focus on interesting/cool core stuff and ignore all the stuff businesses care about (like LDAP authentication).