Where do the "standard" zoom ranges come from?

Just a curiosity question:

Right now, for example, the "standard" zoom ranges are 24-70 and 70-200. Canon and Tamron both make those in a variety of flavors. However, the magic drainpipe is... 80-200, and I'm guessing it was "matched" to the 28-80 in another thread here (and a lot more normal zooms seem to have started at 28mm in the past, like the 28-135). What caused the change? There are other OLD lenses I see references to that are at focal length ranges that I don't see these days (70-210, 100-300, and others I can't remember now).

Similarly, while 18-55 makes sense as a kit lens, of course... why do both Canon and Nikon drop to 17mm at the wide end for their f/2.8s premium crop zooms? I mean, why exactly 17... why not 16, or 15 say? Why leave the long end at 55, exactly?

Might be a silly question, but it's been bugging me, and I'd appreciate it if there was a bit of history there that anyone could expound upon.

In the old film days primes were king since zooms were always optically inferior. As zooms became more popular and more optically sound, their ranges increased. 35-70mm zooms were popular, and then 28-80, and then 24-70, and so on. It's more difficult to produce a zoom that starts wide, and so we see the trend go from 35 to 28 to 24 and onto ultra wide zooms, etc.

Another factor is crop on DX. Canon makes a 15-85 since 15x1.6 = a very neat 24 and 85x1.6 = 136, both popular focal lengths.

Take all this with a grain of salt though, these are just my educated guesses

Vivitar Series I. The first quality zoom 70-210 a 3X. I guess they picked 70 as the start of the range, since everyone had a 50 prime anyway. 3X got them to 210. Maybe is a rule of thumb that you can get decent optics in a zoom up to 3X. Sigma has a 50-150, a 120-300 etc.

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