20-years in the industry and counting, and I've never even MET a "technical product manager".

I have met a handful of people who somewhat thought of themselves as technical. Because they did a touch of Visual Basic or something in their first job out of school, before immediately washing out and pursuing a non-technical career. Some of those guys liked to talk loudly about how much they're "one of you", and "get it", etc.

Without exception, that subset of PM's/PO's were absolutely dreadful to work with as a developer. I would ONLY want to work with a non-technical PM/PO, who stays in their lane and is comfortable with their role.