We all want to go fast, so do cars, but there are limits for safety, and for children and elderly those fast bikes are a hazard. My own 89 year old father was hospitalized for a week, because a fast biker hit his arm so he fell, maybe even without noticing, because he just continued as if nothing had happened.
Where I live city bikelanes are typically narrow, because the roads weren’t designed for them originally. Narrow lanes and high speed is clearly a problem for vulnerable users of bike lanes, and can be an outright terror.

So just don’t be inconsiderate of other users of the bikelane, because it can have dire consequences for others than yourself.
That said I know slow bicycles can be extremely annoying too when they don’t make room for one to pass safely.