Interesting, I have heard this already many times from bike shop owners here in Germany but in my personal experience I have not seen/felt more crowded bike lanes (and I ride a lot). Purely anecdotal, however.
I observed much more crowded bike lanes (in Hamburg), especially during the morning commute between 8 and 9. There were bicycle traffic jams in places where none were last year.
Also, I observed lots and lots of blue-tired rented bicycles during the summer, though their numbers seems to have reduced a lot since the weather got wet and cold.
The blue-tyred bikes are long-term rental bikes from https://swapfiets.com . They're a good deal for someone who is only living somewhere for ~6 months or less.
Also, I observed lots and lots of blue-tired rented bicycles during the summer, though their numbers seems to have reduced a lot since the weather got wet and cold.