I cannot believe how absurd and out of hand this has gotten.

Why did we not all standardise on some _well_known. subdomain or similar for these dozens of records?

The part that gives me an eye twitch is so many domains have multiple verifications for the same group, your own example has Google three times for example. The reason being one marketing company sets up Analytics. A few months later, a different company expects to be authorised to run another set, but all the admins get told is "you have to add this record".