All this is true. Due to various uncertainties, IEC introduced standards with well described procedures and equipment to obtain reliable and repeatable results.
Concerning radiated emissions, starting at 30 MHz is not correct. I took part in an interesting emission test of a small uP driven telephone echange. Its clock harmonics and subharmonics were radiated far away from ~1 MHz up to >50 MHz as a many-line spectrum.
With lots of digital hardware used often without any technical consideration, we now have an exceeding and growing interference everywhere. To get money, fools promoting "digital over power lines" radiate a heavy mess around, filling mainly short-wave bands with their well-paying traffic.
And there is no legal defense- maybe we can equally well interfere with their traffic...