"Practice Interviews" are a thing. Have you considered trying such out?
I haven't done a practice interview, but another poster offered to help me with that. I may take them up on their offer.
This experience is not even at odds with the original quote from the recruiter - when the recruiter says "qualified", all they mean is "able to succeed in the hiring process companies are using". Unfortunately, that definition of "qualified" often doesn't have much in common with the usual definition of "capable of doing good work". The parent commenter may well be qualified in the second way but not in the first.
It's unlikely you'll get a response like that after a 'no hire' from legit companies. They avoid giving that kind of feedback because of legal ramifications.
I always ask for reasons for the rejections, but I rarely get a response. Some will give insight (as I stated in my original comment) but the vast majority will not tell you any reason.
I am just offering a piece of data to refute the "negative unemployment" claim and its ilk.