Unlearn everything? How about just learning to ignore it?

I would bet that the stuff you learned is clouding your abilities less than you think. Rather, you likely just started out like gangbusters simply because your mind was enthralled by the novelty of LD'ing and, when the novelty wore off, your mind lost interest in supporting your efforts... your mind being your unconscious plus your own self-awareness, of course.

In other words, all those techniques did not impair your ability; learning them was merely coincidental with the novelty wearing off -- had you never learned a new technique, you still might have found LD'ing more difficult over time. Ultimately successful LD'ing cares nothing about techniques, and everything about the condition of your self-awareness, memory, and expectations/intention. Success is all about you, and not about the techniques. By extension, blaming the techniques will only slow you down.

I have an old thread, Lucid Dreaming Fundamentals, that might help. You might want to check it out.

tl;dr: Don't blame the techniques, because in the end they just don't matter, no matter how many you know. Success is all about you, and the state of your own mind.