Which format for tiktok, instagram, twitter and so on...

Hi, I have a YouTube channel since this year with around 6k followers. I upload 2 videos in a week. The videos are 16:9, 4k resolution. And around 2 to 5 minutes long. Now I wanna upload them on social media too, I made the accounts already for tiktok, instagram, twitter, and create a facebook site...

The question is, does the format matter? Can I upload my 16:9 videos just on those platforms? Or should i for example on tiktok and instagram cut it to 9:16? Since it's more of a smartphone app. Does this even affect the views? So if I i would upload the 16:9 you can still made it fullscreen and turn your phone, but maybe tiktok and instagram will it not boost it as much as if it was a 9:16, you know what I mean?

Thanks