Really? For me rspamd blocks at least 15 spam emails a day, usually from China or Russia. An additional 2-3 go to the junk folder, and some still slip through the cracks especially if it's coming from a gmail address.
But it could be as simple as it being because my email is publicly available (github, my website, etc.) so scrapers are picking it up.
I agree with the sentiment, when things get too popular every sub becomes more generic and filled with recycled or low effort content. But there's a happy medium. It would be nice if there were enough people that some more niche communities had activity.