I've never used Facebook (or Instagram or any other Facebook technology - as a web developer I've even eschewed React in favor of Vue), so I'd say you don't nee

I've never used Facebook (or Instagram or any other Facebook technology - as a web developer I've even eschewed React in favor of Vue), so I'd say you don't need anything instead of Facebook. Google on the other hand is a bit tougher for me. I use Firefox instead of Chrome. DuckDuckGo instead of Google Search. iPhone instead of Android. Apple Maps instead of Google Maps. I still use Google Docs, but only for working on files with coworkers - I don't have anything personal in Google Docs (I use a variety of other tools like Evernote and Excel for personal stuff). The one I'd like to move away from, but haven't found a good replacement, is Mail.