I don't want to defend this but rather explain this. Legally we are neither pedestrians nor normal traffic. But there is no explicit law for cyclists. You have to be both and it depends which situations it you are in, which typically falls under when it is most advantageous (or safest).
Specifically to the traffic signals, I'll illustrate first. The only time I have been struck by a vehicle while on my bike was while I was in a shared space (marked with sharrows) and waiting at a stop sign (I've also had cars come into the bike lane and hit/almost hit me, but that's another story that every cyclist has). Statistically this is actually the most likely place to be hit (motorcyclists know this too!). So why do cyclists not stop at stop signs? Because sitting at a stop sign is dangerous. Because to cross the intersection with momentum takes 2 seconds instead of the 5 that it takes when stopped. You are reducing your chance of being struck. This is why you won't see cops pull them over either (unless they are pulling into traffic, which is a different issue). Having momentum also SIGNIFICANTLY increases your ability to dodge things. You are absolutely the most vulnerable when you are not moving. To be safe on a bike you want to keep moving. We can't accelerate away from dangerous situations like motorcycles or cars. Humans don't have that kind of torque. It isn't just laziness or wanting to get to places faster (I'll give you that this is part). If you aren't moving then you are more vulnerable.
Cyclists that are breaking the law are generally doing it from learned behavior to increase their safety. Another common example is riding close to the middle of the road on shared roads. I cannot tell you how many times someone has opened a door on me. I've hit more than a few (most often when in I'm in a bike lane!). Both in day and night (when I have a fucking light that I directly aim into peoples' mirrors to try to make me more noticeable!). It's just easier to ride closer to the center and deal with the driver behind you that is upset and should be on the main roads anyways. Also, lots of dirt and crap accumulates in the bike lanes, so that's why we frequently move out of them. Frequently there's also gutters that would cause us to go over the handle bars.
Frankly, I value my safety over your convenience. That's what it comes down to.
> [the ones that] drive on the road correctly are merely annoying because they hold up traffic and disrupt speeds, which is dangerous
And we all agree. This is why you should argue for not just bike lanes, but protected bike lanes. But frankly most cars don't care about bike lanes and treat cyclists like second class citizens and disregard their spaces.[0]
There are plenty of cyclists that are idiots and doing dumb things that will make you question how much they value their life. But I want others to also realize that cyclists also develop other patterns that may not be straight forward to drivers. Understanding each other and the vulnerabilities we face is how we make everyone safer and how we inconvenience each other less.