I’ve had the same issue, it’s critical to get fans to cool your MacBook pro since they are not capable of cooling themselves under load, especially i7 or i9.
I have cabinet fans under mine and it works great, just don’t ask me to use a MacBook Pro as a laptop.
And if not fans, I actually just elevated my MacBook Pro on a cooling laptop stand (with no ventilation) and that was enough to keep it cool for hours-long streaming.
I have cabinet fans under mine and it works great, just don’t ask me to use a MacBook Pro as a laptop.