IIUC, macOS uses NetBSD's userland though it has FreeBSD bits in its XNU kernel, so there must be benefits to NetBSD beyond its portability that I am just not aware of. :)
Incidentally, hasn't Linux been ported (eventually) to more architectures than NetBSD has?
The kernel? Or a full-blown OS like Debian GNU/Linux? Official ports, or also unofficial ports?
If you're going for official Debian GNU/Linux ports, then no. If you mean Fedora (say you really wanna run Fedora), then no.
NetBSD isn't just a kernel; it is a full-blown, portable OS. The base system is practically the same on every port. So if you're familiar with NetBSD, the idea is that you can always run that familiar OS on another computer.
Linux and other FOSS software becoming popular makes using NetBSD a lot more convenient, not less. There's a top tier FOSS browser that will accept NetBSD related patches, several really good document editors, graphical tools. We can even take some driver code from Linux itself.