Probably not what you’re looking for, but when I had a somewhat unstable internet connection, I’d just self host for myself as much as possible to reduce my reliance on the internet. I ran lancache to cache as many updates I could. I’d download kiwix archives at university and host them at home. I had ripped hundreds of DVDs for Jellyfin and I’d even sometimes record shows off of free to air TV with TVHeadEnd. I also self hosted languagetool (a Grammarly alternative). Although, I still do all that (and probably more) with stable gigabit fibre (except I no longer saw any point in lancache).