Not sure any of it is going to brick hardware, but I haven't played with setting flags with ethtool. I've messed with Wake-on-Lan stuff in the past, as well as "prevent device from randomly waking from sleep" issues, too (on Windows, though).
I do have the advantage of a lot of past experience with Atmegas then RPis, so know a lot of the common sense hardware considerations... and a lot of troubleshooting. For me getting 90% correct with ChatGPT, and building up incrementally, has been an improvement on doing it all myself with google.
I might take an attempt at asking chatGPT how to do what the author did. Could be informative, even if just introspective realizations like, "oh, this is a question I asked in a good way due to my existing knowledge."
There isn't much info on the internet about it. Of the info that exists most is inconsistent, outdated, and/or wrong. The specific instructions need to depend on what's supported by the exact model number of your network card. You're dealing with hardware, so there's a chance of breaking things permanently. Close has zero value, the solution needs to be exactly right. Close but incorrect solutions are hard to debug.