Most statements made which rely on having to make such obvious generalizations are open to scrutiny. I’d go further and say that they positively invite scrutiny - as you are doing, and that’s tremendous..
By scrutiny I mean asking further questions and doing research into not just the brands but knowing a bit about each feature of tube amplification. You need to know how the transformers are constructed and how many windings and other technical things. Issues that may be not so relevant to solid state amps..
That's just one trite example of many possible issues.
This might freak some people out and there are specialist forums which may be informative.
Country of manufacture is a signal as to quality but is about as big a generalization as anyone could ever make (and sometimes they can be very accurate, of course, but rarely) and so back to my first statement.