ASR measurements are mostly based on gear that costs $1,500 or less, in great part because most reviews are based on forum members that send in their equipment to Amir, or companies whose equipment is affordable and they hope they can garner a good review. Most who own very expensive gear are not going to be inclined to ship their stuff to AMIR, so we do not see too much of that tested here.
At the end of the day, Stereophile has to turn a profit by selling subscriptions and ads, and the user base most apt to make that happen is made up of folks with very high household incomes. I would suspect Stereophile's subscribers earn on average more than 200K per year, with many way beyond that. The magazine throws in a few sub 1K products to keep some lower income cohorts a bit interested.
ASR exists due to the benevolence of Amir, as he is not making money on the site and also puts in a huge amount of time to test and report on equipment. When he burns out or turns his attention to other matters, things could dry up. All other magazines and sites are out to make a buck, which is capitalism. We kind of get a free ride at ASR at Amir's largesse. That does not happen at this scale anywhere else.