Video/Audio settings for Social Media

So i decided to start recording some videos at home playing original pieces and covers to share in different social media platforms. The thing is that in the past i always had issues with Instagram (among others) compressing my videos when uploaded and then both the quality of the video AND the audio become pretty bad...

I know that social media platforms don't support 4K videos. So i tend to go with 1080p instead, but in the past i've tested both and sometimes, yes, the 4K videos were destroyed by the compression, and other times, they ended up looking better than the 1080p ones.

So my question is, what is your experience? Do you usually export videos in 4K or 1080p to then upload on social media? What about framerate and bitrate?

Also, what about the audio? Any tips on what to do to avoid compression as much as possible? (Ex: volume/LUFS/db... 44kHZ vs 48KHZ.)

Any advice would be highly appreciated.

Thank you!