It's an expression common in the UK when you feel pressed to make a relevant comment but intend it in a not unkindly fashion.

To answer your question, it's partly because Americans have a reputation about not travelling overseas much and therefore being a little naive, and partly because on the one hand there is the reality of what we living here see, and on the other the tourist world brochure where shiny happy people abound. The OP seems rather too close to the latter at times, and may give a slightly misleading picture.

There's also the point that the bicycle infrastructure is not as highly developed as it is in the two relatively small countries he's visiting. In the UK there are far less paths, the road surfaces are dreadful, and, in the larger cities anyway, cycling is marred by the backlash of urgent commuters cycling on pavements, often, if you believe the papers, seriously injuring innocent pedestrians. In France the infrastructure is better, but cyclists are not separated from the traffic as they are in the Low Countries, plus, in the sticks, unless it's a canal or river tow path, you'll be on the road most of the time, albeit without much traffic. Generally motorists have a better awareness of cyclists, but you'll still get knocked over on roundabouts where all you'll get is an apologetic wave afterwards. Germany has good paths in many cities plus motorists who obey the road rules more that in most other places, plus some stunning bike paths in the Black Forest/Danube/Rhine regions, but on some you'll need an mtb rather than a simple touring bike. In other words, every country has its own ideas re cycling infrastructure.

There's also who is cycling. Certainly locals cycle to the markets and supermarkets, and the commuters commute, but here in the small town where I'm currently living you'll see more people in full lycra doing their fitness run - I know, I'm one of them Numbers? about 10-15 cyclists per day compared with a minimum of 10-20 times that in cars. On the Riviera the ratio expands way further until you get to Cannes where there's a double-lane bicycle path taking you into Nice mostly packed with people cycling in pelotons, but even that is on weekends only.

I'd add that cyclists in many European countries are envious of the Dutch cycling infrastructure. It is eye-opening. Having lived there for a couple of years I never had the need for a car and while it's true you can cover most of the country by bike, if you can't, a train will get you close. That's the other corollary about travel in Europe: the train networks are highly developed which is handy for cyclists in the larger countries such as France, Spain and Germany. That said, the automobile rules here just as it does in virtually every country where people can afford them, and people spend many happy hours on the Périphérique going to work.

Hope that rambling response answers at least part of your question.