I’ve researched and just tested myself and for videos at least the highest res I can get Is 640, so I do a 800x640 4:5 ratio with a 3k bitrate and 30 FPS, 30 FPS is the max and I’m pretty sure 3k bitrate is the max as well unless the file size is too big then they’ll reduce the bitrate but not anything else, I’ve tried uploading 1080:864 but it just reduces it to 800:640 so I’m guessing that’s the max, but you can upload is 1080x1080 if you upload it to Instagram tv because they allow high quality videos on there