You sir, are a complete idiot. I am both a cyclist and a motorist. Not many cyclists are "Trying to squeeze between a 20 tonne truck". In fact, I was nearly killed recently by a van driver who accelerated aggressively up a road, caught up with me exactly at a left hand junction, and swung a left directly in to my path. I believe he was on his phone. I wasn't trying to squeeze between anything.
When I am driving I don't swerve into cycle lanes, I double check my left mirror, and I indicate. Unfortunately a lot of motorists don't do this.
This is not to say there aren't some idiot cyclists. There are. But your sweeping statement comes from a position of pure naivety.