The UX "cringe" you speak of was/is a real methodology to product engineering. You'd have a number of personas, the user being one of them. A lot of the time you'd have more specific user personas, or even have fake names for these people who had different wants and needs from your product.

Then when brainstorming on a team, you'd start with "as a user"/"as an admin"/"as a Power-User"/"as Eva" and then use the first person. It framed the product story as something requested by that person.

Was just one way to go about it. Idk the origins of it though but it dates back to at least 2010 if memory serves, probably way before that.

This is true, but it doesn't make it less cringe inducing. Even when discussing actual requests from actual users, we don't pretend to be them and talk in their first person point of view. We just say "Eva wants to" or "admins need to" etc.

I'm not saying that methodology is cringe (although making up people totally is). I mean how they write out the sentences like "As a user, I want to ..." instead of just having a table of features with a column for the target user type.