Shooting I'm square crop has been a thing for a while now, it means clients can re-crop the same footage for different outputs. And usually means framing is a nightmare and never really works out well for any of the output formats.

Why would you do that? People don't even watch shows in portrait even when they use their phones. They watch short form content designed to fill idle moments. It is nearly exclusively bullshit filler or one person content. Real content will continue to be viewed in landscape forever.

Just forget about rectangles altogether, circular video is where it's at!