I cant help you, but I am curious. Do you require
hashcat for any particular purpose other than an educational/hobbyist one?
I suppose what I'm meaning to say is that if you have a genuine need for such a tool (ie. for study or employment) then perhaps NetBSD isn't the appropriate OS for your use case and you might want to consider booting a kali/parrot vm? In fact, I can't think of any other reason why someone would need a system (installed to disk) that would require such tools. Most white hat hackers and pen testers will boot from live USB's or use virtual machines (same goes for black hat hackers too).
That said, I've asked for plenty more useless tools to be included in
pkgsrc and nobody questioned me about it so feel free to tell me to mind my own business 😅