Top down or bottom up? Just asking...

Now, wouldn’t it stand to reason that ’other things being equal’ a 20-30k speaker from Wilson or Magico would be better than the same from the other firms?

Please clarify.
What are all the other things that are equal in your comparison?
If you are simply referring to the price where two distinct speaker brands cross each other at a specific price point, this is a false equivalency.
Cabinet design and construction, drivers, crossovers, implementation, company philosophy, marketing strategy, etc. would all need to be the same for this to be true. Now, if you were to post "considering trickle down technology" in lieu of ’other things being equal’, I believe you would get your point across with more precision.
So yes, it would be reasonable to think that if a company utilizes the strategy of trickle down technology from a higher end product, that product may be superior to another companies at a particular price point that had no such higher end product. Or not. Too many differing variables.

'Other things' = first and foremost personal taste. I'm very fond of MA; some people really dislike Magico or Wilson. 
But also there is the size of the room, the kind of music you like to listen to, even the appearance or size of the speaker itself. 

Ah, now I understand your premise for using that expression. IF all those aspects were similar, what are our thoughts.
I’m sticking with my ’trickle down technology’ spiel.

Actually I like both at the same time ... ;-)

It still all comes down to personal taste. I could easily see someone preferring Paradigm’s top offering to whatever Sonus Faber, for example, has at that same price point.

The bigger issue, I think, is that Paradigm has a much harder hill to climb scaling up than it is to scale down in large part due to brand perception. I shook my head when VW launched the $100,000 Phaeton and new it would fail from the get go. The Phaeton was actually an impressive car, but are you gonna drop 100 grand on a Volkswagen when you could have a BMW, Porsche, Mercedes, etc.? It’s precisely why Toyota, Nissan, and Honda created Lexus, Infiniti, and Acura — they knew perception matters, a lot.

The benefit to scaling up might be that as higher-volume manufacturers they can possibly leverage their cost advantages in creating higher-level products theoretically giving them even higher margins selling high-end products, but it doesn’t matter if people won’t buy them in sufficient numbers.

Case in point, MA’s top speakers are by all accounts fantastic and a great bargain for the performance they deliver, but they don’t get near the attention of the Wilsons, Magicos, etc. at their price points. I believe if MA launched a luxury division with a nice new name and raised their prices their top speakers would be getting a lot more interest and exposure. But, all else being equal and speaking from a manufacturer’s perspective, I’d certainly rather be in the position of scaling down as it’s a hugely easier path than going the other way.  Not sure this answers anything, but anyway...