For the most part I'm with you on everything, but...
Just for the record, 720p can run at a variety of different framerates and still be "true" HD whatever that means. So 60 fps is not actually a requirement of 720p cause 720p can run at 24p, 30p, and 60p (maybe more) as far as I understand it.
Also for the record, there are PLENTY of (in fact I might argue the majority of) DVDs that are 24p, or are 24p stuffed into a 60i wrapper. So, FWIW, when I watch a movie like that on my 720p native HD display, I am literally watching the movie in PERFECT 24p -- it plays at 24 fps with no pulldown artifacts whatsoever. So, I can easily point to two good reasons (besides filmouts) where someone might want to shoot 24 fps. One is if your distribution is targeted to DVD b/c given the right player and display it can literally and actually be watched in 24 fps. Two is if your distribution is to the Net or Web, in which case you can also easily watch the video in true 24 fps. And, of course, yes you get less temporal resolution, but just as some photographers still use film for the "look" rather than digital, some folks may want the look of motion film, which is 24 fps and everyone is used to it cause that's how film works 'til this day. I so don't buy the "stobing" argument b/c if it was that bad, they wouldn't keep spending billions of dollars per year making 24 fps motion pictures. The real issue with strobing is that you can't shoot 24 fps like you would shoot 30 fps, the DP has to actualy shoot differently, especially slower pans. Also, it is worth mention that there are many, many shows on TV these days that are showing you 24p material wrapped into a 60i signal. Now yes, the tuned eye can see the funky cadence, but the fact remains that there are tons of examples on MTV and eslewhere where they are shooting 24p on DVXs and pumping that out the NTSC pipes, and they do it cause they like the feel of it. Not everyone does, and myself, I only like 24p when it can actually be watched that way, as opposed to watching it with 3:2 pulldown inserted at 60i.
Lastly, I totally agree that HDV is HD, so no arguments there, but I do get a kick out of your analogy that uses audio to make your point. The reason I find that amusing? Is because the HDV codec records audio in a LOSSY format -- yuk! That little fact often gets overlooked, but the reality is shooting standard DV gives you 16/48 lossless audio and HDV gives you lossy.