The amateur level in France is easily teh 2nd best one in Europe, and by far: I used to play with foreign students from Germany, Belgium, Sweden, Denmark, Russia or Portugal while being in college, in the 90's Belgium was awesome, better than Germany, but they've lowered a bit since. Sweden has always been strong in really low local divisions, but when it comes to national amateur level... it's difficult for them.
The national amateur leagues are definitely the best in Germany and France when it comes to Europe, just think of this: in 2021 the Lebrun Bros. were playing for their native club Montpellier who was in Nationale 1, the 3 tier and 1st non-pro league, they still couldn't make it to the Pro B because Lille Metropole beat them with guys like Joao Monteiro (POR) who was WR 78 at that time. Yep, it's amateur level, believe it or not.
From the Regionale 2 to Nationale 1 there are 4 divisions, and it's a tough battle every week-end, some guys ranked in the top 1000 sometimes play for clubs involved in regionale 1 leagues because they're offered some coach jobs, or even regular jobs. Then the level starts to drop a bit in regionale 3 to the lower ones at the local level.
So I would say
1- China
2 - Japan
3- South Korea: less players than Germany or France but the amateur level in lower local leagues is better to me. Also TT is a way more important sport there than in european countries who are more focused on football, tennis, athletics track and field, handball and volleyball.
4- Germany of course
5- France
6- Russia
7- It's hard to say if it's Belgium or Sweden, because unfortunately most of the elite players are gone to Germany or France.