[CMay]

That can be an issue, but also if you're streaming then you're probably doing so in landscape and having your display configured in portrait just seems so much more productive.

You can compensate by having a much higher resolution landscape display where certain windows are portrait, but the text won't be that readable on stream without dynamic zooms.

I think the real value is that if you're having motivational issues and streaming gives you more consistent motivation then it may offset the downsides. Writing some code in a suboptimal environment is better than writing no code in an optimal environment.