This seems extremely elitist, even if just for the fact that you do not know what other knowledge (and experiences and viewpoints and...) those people who'd be interested in those communities would bring.
If you want a site comprised entirely of - what it seems to me - techbros who talk about how large their homelab Kubernetes clusters are, you should do that by curating your experience with the general platform, not by excluding anyone else, which is what you're doing here even if you don't realize it.
I personally want people from all walks of life to set up shop in the fediverse (as long as they're not jerks). Even if I'll never see or interact with 99% of what they create, maybe that last 1% will solve an obscure problem I encounter, or recommend me something (whether it be a product or recipe or location or...) that will change my life for the better.