Meta (FB) doesn't ban links to blogs or other social media but heavily throttles (lock it) it until you start paying for it. Here is the comic that explains it better
https://theoatmeal.com/comics/reaching_people Also, links are not clickable on Insta. Similarly, WhatsApp also block if URLs/images/vidoes if shared too many times (at least in India, there is some rule or something like that for Fake news, I forgot the details but they use AI and mods to throttle WhatsApp for sure )