Thank you for this excellent write-up.
It’s interesting to see the inclusion of “Product Manager” as a type of UX Designer. I do think the world needs more design-minded Product Managers — most PMs I know have business degrees/MBAs or CS.
From my (limited) experience working on product teams, the PM is the one responsible for execution, they need to balance design, technology feasibility, and business needs. In a B2B/Enterprise product context, in addition to doing research and requirements definition, they also work on the business process around the design to make sure that the product gets released, e.g. Pricing model, Go to market strategy, internal training, documentation, testing, etc.
In the end, no matter how well your design is, your job is only done when it get into the hands of your customer (and even then it’s not done). That’s why — this is a thought I had recently — instead of learning how to code, designers would benefit more from learning about the business and have the mindset of a Product Manager. Knowing how design deliver value, how to sell your design, and what would get it to user’s hands are important skillsets to have.