Yeah saying its running hotter because of a exhaust heat isn't exactly a great analysis.
No mention of fan RPM, temp probes at specific areas where changes were made, no temp probes in surrounding areas suggesting system wide increase thermal levels, and no mention of improved memory cooling or testing to confirm.
This could easily be just as efficient, yet cheaper, and solved by the fact its fan is running faster. It's silent as it is and an improved fan could provide more direct airflow at similar RPM. They definitely have room to spare in noise to reduce temps.
What a half assed video from such a YTer. You'd expect more from someone like Austin who's been around for a long time. This was basically a just first initial thought say what I think don't test anything to confirm lets get those views type of video.
If someone had a Dev kit software we'd be able to tell more information, but that ain't gonna happen. Gamers Nexus will probably do it right. I'll await there confirmation.