The way actual 3 letter bureaucracies work here in the US, who is president at any given time makes very little difference. This is especially true of niche areas like audio (as opposed to, for example, high-profile medical issues). XXX's remarks are reasonable, but IMO will only serve to make the specifications even more difficult for a consumer to understand. What the consumer actually cares about is, "Which of these two amplifiers I'm comparing will play louder with my speakers?"
There are (at least) two different issues: first, the standardization of the load. 8 ohms was something reasonable some years back, but it appears to me that a higher proportion of today's speakers tend to run to lower impedances. But that, of course, is the least of our problems- except for a few exotic choices (e.g., Magnepan). loudspeakers are usually reactive loads having highly varying impedances with frequency. And no two appear to be alike. There are certainly examples of amplifiers that are perfectly happy with resistive loads, but start having issues when the impedance starts swinging. In cases like that, a lower power amp with better load tolerance will be able to cleanly play louder. So what does the power rating tell the consumer in this case? Basically nothing.
Second, the issue that XXX raises, which is a realistic view of musical signal spectral content. This is a somewhat easier issue to attack- we use sine waves for ratings because we have always used sine waves for ratings. ;-) And this is mainly due to easily attainable measurement capability from a half century ago. There's no reason that with modern test gear and signal processing capability that we can't use something like repetitive pink noise or other spectrally shaped stimulus. Rather than THD, we could rate distortion as the RMS deviation of the voltage between test signal and (scaled) output to the load. This would inevitably pull in source impedance to the measurement for anything other than a resistive load, but that's not a bad thing since, besides low distortion, we want the amplifier to resemble a pure voltage source.
If they allowed me to be dictator of the FTC for a few days, I would probably incorporate a shaped noise source as the test signal, measure average power at a standard value of RMS deviation expressed as a percentage, and rate it at a 6R resistive load and a standardized complex load which would be vaguely representative of a large proportion of passive consumer speakers. The old 1/3 power sine wave preconditioning requirement would also need to be reworked since that's appropriate for last generation amps, not Class D. Perhaps running full power (as defined by my deviation proposal) with the shaped noise for some defined period might be suitable?
Of course, with the market moving toward active solutions, we may be worrying about standardizing the measure of the diameter of buggy whips