For starters; Try GhostBSD - FreeBSD with a MATE desktop.
Developers aren't "scared of UNIX". They are scared of things they don't know, and "don't know" in this context means Google search page doesn't explode with results when they search for the thing.
Anecdotally, people in storage business are much more familiar with FreeBSD due to FreeNAS and ZFS in general, but as some of my colleagues who previously worked for Dell EMC "storage division"^* recalled, the second most popular platform they had to adapt their storage solutions for was AIX... (and that trailed far, far behind Linux). It's also funny, in a way, since internally, they often did use FreeBSD in various departments because of FreeNAS. In a similar company, our home directory on dev. server was backed up by FreeNAS (we were also developing a storage product... for Linux).
----
* - There isn't really a "storage division" within Dell EMC afaik, just a bunch of different storage-related projects. I just had to describe those projects in some way.
> In popularity Unix is not the main OS for most developers.
Because of FreeBSD don't want to be helpful? Had idea of Jails but had no resources to make it usable for developers? What's your opinion, knowing FreeBSD backstage?