One Amp To ‘Rule’ Them All....

Yes, but I can’t divulge that info because I’ll have to pay a premium when I need to replace mine.
And I won’t tell you my favorite surf spot...

The amps you mention are not there.
If we are to take amps that are used BOTH at home and in studios, here’s a list of actuals, not suppositions:
- Benchmark AHB2
- FM Acoustics
- JMF Audio
and the list is not much longer than that. Most amps used in studios are not used at home, and of course vice-versa...
Now one amp to rule them all doesn't exist, but there's quite a long list of absolutely brilliant amps which we have all heard, read about or maybe listened to.
I am using a pair of Gryphon Mephisto and I have yet to see or hear something they cant do!! my other preference goes to Pass XA amps, but I could live with any good amp, from classA, AB, ABH to D. The Benchmark are probably one of the best sounding for the cost, and the Spec for classD...absolutely excellent!!

POWER+cable+PRE AMP+cable+AMP+cable+SPEAKER (set up)+cable+ROOM (temperature, pressure, acoustics)+LISTENER (skill, taste, etc)

These are the elements, more or less, with BOLD more important ... and I ask you op...

How could anything be standard in this? There is no standard.
People who want standards are on the perfectionist side of the spectrum, the scientists side. You all come to music because music is the universal language of humanity. It’s not a science project to set up a room, it’s a journey into the self.  You want to leave your bias in the supossed land of no bias but you are afraid.
Embrace the unknown, and the unknowable. Have faith in yourself, not fear of missing out.

(As far as mastering rooms that use tube amps, I have a successful and well known example right in front of me daily, but yes, they are in the minority as it’s a PITA.)

Benchmark Media Amp AHB2. You will not be disappointed.