You CAN transfer screenshots to your phone with the Switch, this was implemented in an update. So that means Nintendo's servers also host your screenshots and video captures.
Have you ever tried that? I did. It's bad, inconvenient, counterintuive and very often don't connect to the phone, conflicts with Android versions and SOs that blocks the wifi connection
There is no reason to be that complicated and slow. I simply given up uploading my video captures of Metroid Dread