Unless you're famous enough that everything you post gets to the top of Google, no one will read your content unless you post it to a social media platform with a curated audience. Literally no one but bots and AI crawlers. I mean, you have a whole list of crossposting links at the bottom of your own blog posts, including to HN and Mastodon, so you clearly understand. You wouldn't lose anything by limiting comments to just those curated social media platforms except spam and bots.