To clarify one thing, I'm not concerned that they "work in marketing". I am concerned that that the marketing page is fake: it's a bunch of AI generated faces and fake LinkedIn profiles. This does not lead me to the conclusion that they work in marketing at all.
As for your version of the script, it still strikes me as a _little_ weird (why put a self-install inside the .zshrc that is only expected to run once per system you have it on), but clearly far less concerning than the version they have in the current docs.
All code execution involves some degree of trust. There's enough here to make me personally not trust the developer, but if the information here doesn't give someone else the same qualms, that's entirely fine.