As far as I know, things have changed and I think most of the German MI use the bpm for their profiles. It is quite common to teach bpm = rpm and it seems in the Netherlands it is the same. Music has become a part of the clinic by now and the MI explain about the bpm and how to count them.
In the German forum we discuss these things as well, but it is more like if we should use the musical bow (every musical bow consists of 32 beats and the first one is known as the "big one", this indicates a change in the song, you can use it for a technique change or for jumps for example) or not.
Sometimes, I wonder if there is a difference how to teach spinning in different countries. We Germans are not very rhythmic people, so we hear the beat first and not the rhythm.
Your experience in San Francisco is a good example how the beat can be misinterpreted and overdone. I can give you an example vice versa: I took an endurance ride during a spinning event where the instructor played only techno music with approx. 138-140 bpm. Of course, the goal was to find your own cadence and to stay there for the ride. It was pretty hard!! I saw many people bouncing in their saddles, because they wanted to go that fast and there were also a few who made a hill out of it. So what do you think - was it a stroke of a genius or just bad music choice? Music is a motivator and supports you - I found it just the opposite! Ok - you can say you need a lot of intrinsic motivation to go through such a ride - but where is the fun factor?
I wonder how you teach the different cadences in your rides when you don't use the bpm and it is the goal of your class. Do you use cadence checks for that? How often? Every time you change cadence? It is great if you have a spinning computer, but what do you do if you have not?
Another question: how important is it to teach a certain cadence at a time? What's the use of it if you are just a "normal leisure time spinner"? If a certain cadence stands for a certain heart rate, then ok, but here I would say heart rate depends more on the type of music selection.
I agree with you: beat is not everything - but it helps a lot, especially those who are not so experienced.