My opinion is that FreeBSD is one of the best choices for NGFWs, due to the distinctive behavior of the OP system itself.
However, you can't run it cleanly on FreeBSD, so like pfSense, sticking to the parent basics (FreeBSD), you need to implement a different philosophy = pfSense.
NollipfSense /
I agree with you that the future belongs to the VM, but we still have a lot to learn in this area.
What is currently worrying is that only mirror solutions can create large stability systems.
I currently work for a world-wide insurance company, in the current unfortunate situation (COVID), more than 8,000 employees work from home on a VM basis.
It works, but 25 extra mirror servers have been set up in 15 countries to eliminate the any possible problems.
Virtualization is a wonderful part of the IT world, flexible and I hope there will be more and more serious availability.
(I started with Windows NT servers and Win 3.1 has changed a lot since then :-))