I'm with you. It was a throwaway comment in that the garage wasn't exactly well kept and there were worse places for a rough installation. I'd suggested trunking as the ideal option from my first post, but hadn't watched the whole video to know whether there was a good reason for not doing so - regardless, flexible conduit seemed like the least best option!
Given the guy had just done a rewire the homeowner may have dumped a lot of stuff in the garage out of the house
Trunking would have been my first choice,
The flexible conduit may have looked a bit better if he hadn't cut it back short as the bend above the CU looks like he didn't have enough tube and the way he has tram track fixed it with saddles makes it look even worse, it would have looked much better if they were bunched together and an all round band "saddle" used