Czechia is said to have progressive system here, but it actually has a flat rate (at least if our own Ministry of Finance is to be believed). IIRC the same is the case with Poland.

50 countries is stretching it, isn't it? TBH I meant EU (27), but I don't even know what are all the 23 other?

The Walpiri would disagree - https://numberwarrior.wordpress.com/2010/07/30/is-one-two-ma...

I'd call seven "many". Many is more than "a few", which I'd say is =< 5.

The total number of countries (50) only matters if you're using relative terms, like "most".

I disagree that the total number does not influence the usage of the term many.

In the middle of the desert outside of a population center, one might call a group of 6 people "many", but one would never use the same term to refer to 6 grains of sand.

The total number is very important. Otherwise you could say: many (insert minority group) commit hideous crimes.