I subscribe to his newsletter and watched the vid the same day also. Loved all of it, as I do most of his videos.
Early last year Tony Northrup*
did a similar video on ISO not being as much a contributing factor to noise as aperture and shutter speed. He showed pretty convincing examples and, like Perry, discussed how ISO is not really a measure of sensor sensitivity. The basic take away I got from that and Steve's vid is that for the least amount of noise it's best to use the slowest shutter speed and largest aperture you can for any given shot, rather than raising ISO first.
*Not to veer away from the topic but I don't understand the vitriol I've seen at times directed towards the Northrups, from here and elsewhere. "
I see the name 'Northrup' on a video and I immediately dismiss it" is a sentiment I see surprisingly often. I just don't get the enmity. When I decided to get into digital photography in 2017 I took their advice on what DSLR a beginner should get (a D3300), watched a 1 hour tutorial from Tony on its features and functions, then spent more hours watching their tutorials on lighting, composition, gear, etc. I learned a lot from them, as well as from Mr. Perry and Matt Granger. My own guess is that because of the sheer volume of content he puts out, including opinion and commentary, there will always be things someone will disagree with. And this being the internet, when you disagree with someone they are automatically despised, practically. Or maybe it's their delivery? Their camera presence? Whatever it is, it sure seems to distract people from some useful and practical advice backed up by real examples. /soapbox