I guess that’s the kind of advice that I’m trying to avoid. I can understand and appreciate someone telling me to be more assertive, take care of myself physically etc. and I’d have no problem with it. But a lot of the pickup artistry stuff goes beyond that into things that even I can tell are unhelpful.

I think there is some valuable advice in there that goes beyond simple pickup artistry. Maybe you just subconciously do the mistake to "present" yourself in the wrong light.

It sounds like OP is trying to find a romantic partner, as well as a way to improve himself - not just someone to fuck.

You need to learn to walk before you can learn to run.