First of all, they've self identified as non-American and presumably not a native English speaker. You could have presented the difference between drive and ride with less pedantry.
Secondly, cities with large numbers of cyclists tend to have better, not worse traffic. It's obvious why: fewer people driving plus infrastructure for bikes is developed and separated from car infrastructure. You should wish for more cyclists, not fewer.
Unfortunately, you can't escape the need for pedantry as a native speaker, and as a non-native (which I sssumed they were), I generally find they appreciate th clarification.
Arguably, what makes motor traffic "flow better" is increased predictability, and decreased demand on shared infrastructure. I'm not condemning all cyclists or saying it isn't worthwhil; merely that the arrangements we've got with them being sometimes pedestrians/sometimes road users leads to a cultural clash that leaves everyone frustrated.
The entire urban network architecture leaves quite a lot to be desired.
Secondly, cities with large numbers of cyclists tend to have better, not worse traffic. It's obvious why: fewer people driving plus infrastructure for bikes is developed and separated from car infrastructure. You should wish for more cyclists, not fewer.