I've been thinking about this today (sad sack) and I have come to the following conclusion: the AIBU was about whether the OP WBU to "bloody hate cyclists" and the answer is that it depends. I think we are all talking at cross purposes and of course are also talking based on our personal circumstances and experiences.
Firstly, what cyclists are we actually talking about as like drivers, they aren't a homogeneous group. There are people using their bikes for daily/occasional travel from A to B as they like cycling, or can't afford a car, or don't want to add pollution/congestion. There are folk that like to go out for a family rides to get fresh air and exercise. There are the individual hobbiest road cyclists, there are mountain bikers, there are group/team cyclists etc. So, to attribute the same characteristic to all these groups, positive and negative doesn't make sense.
For instance, a decent proportion of cyclists will also be drivers, an amount of those drivers will be driving the biggest polluting cars, some will be driving to get to where they want to cycle. Some cyclists come hurtling down footpaths and tracks in the woods at 50mph etc with no regard for pedestrians (i'm sure this is enjoyable to them but they will come off as badly in a crash as anyone they hit). Some cyclists like to dictate the speed that everyone else gets to travel at just because they can and will argue their right to do so, even when other vehicles such as tractors etc will pull over. Some cyclists disobey the road rules, switch from road cycling to being a pedestrian (still on wheels) as and when it suits them. There are equally a vast majority of cyclists who are just going about their daily business and get abuse and dangerous passes from drivers and pedestrians for no reason.
So It's not unreasonable to hate some cyclists in the same way as it's okay to hate some drivers.
Giving the different numbers of each on the road, I honestly think that there are a disproportionate amount of cyclists causing issues compared to the amount of vehicle drivers causing issues, but I say that as a driver so come from a position of bias....I'm sure someone could did out the stats. I'm sure I remember seeing some shocking ones about the number of accidents caused by jumping red lights and when you extrapolated the data there were many more caused by cyclists but it's difficult to say as you can't ever say exactly what the proportion of bikes on the road area at any one time which is easier to do with cars as they are registered.