Don't disagree with you that using TrueNAS Core as a general server/VM platform (some other things as well) has pain points. Some of which are BSDisms, some just as you say due to the plain fact that the community is vastly smaller. Even simple stuff like ports frequently being a bit out of date, or lacking the diversity you'd find elsewhere. Nothing that can't be worked around, but always some extra time on a whole different thing which in more popular environments (be it Proxmox/KVM/ESXi or whatever) would just be there and then get out of your way.
That said I do think though a NAS is one of the things, even in a lot of homelab environments, that's actually worth its own hardware separate from the VM if one can swing the extra cost & space. I virtualized NAS for a while too but since I wanted to run VMs themselves off the NAS as well as a lot of other stuff, have a good backup/restore story etc, I found it started to get unpleasantly circular in terms of bootstrapping from a cold start or restore. Also, the hardware requirements for a good NAS are fairly distinct from a lot of what I wanted for virtualizing. It's not impossible to cram lots of hot swap drives and full size PCIe cards including GPUs for passthrough and tons of CPU and tons of RAM into a single 4U by any means, but splitting things out made it a lot simpler to optimize each side better. The NAS could be smaller, cooler, quieter and good at its own thing. After all-in-one I ended up with 3 distinct boxes: router/gateway (OPNsense), VM system, and NAS system. I know others have gone totally different directions, from AIO boxes to wild K8s clusters doing it all, but I feel like those provide a decent balance of flexibility and stability/isolation, I can mess with stuff and feel confidence in basic network connectivity or storage. Isolation also means not feeling quite the same pressure if one platform isn't as good at something as another, so long as it's good at its own specialty.
>TrueNAS Scale, which is based on Debian, I think reflects an acknowledgement of the pain points of working around BSD for the types of services a lot of people want to use their NAS for.
I'm a bit bummed philosophically there. I've used BSDs for a very long time, like much of the philosophy if not all the warts, and fundamentally losing diversity in software platforms even if open source is concerning. At the same time it's hard to get around the raw power of network effects in tech, and Linux has a ton of resources and eyes thrown at it at this point. I have no plans or interest in moving in the near future either, but it's hard not to feel like the headwinds are building a bit for TrueNAS Core. Though FreeBSD continues to put out excellent releases, and it's gotten this far. I've found myself on the underdog "but I think it's technically better!" losing side of a lot of tech in my life though :). It's always a balancing act in how much it's worth working on a tool itself vs using the tool to do other work.