AdAway (in F-Droid) can block with /etc/hosts (no VPN involved) if you have root. The hosts blocking still works even when connected to a VPN. Aside from loading ad domain lists into /etc/hosts, it also allows you to specify custom domains to block - I personally have Reddit and HN in there :)
You can use IronFox - available in Accrescent store that comes with GrapheneOS, and install firefox extensions
This doesn't answer your question, but in case it helps for others out there: it's possible to use WhatsApp with no access whatsoever to your contacts and I used it that way for years. Connecting with people is slightly jankier but it still works.