Especially since i see similsr statements go unchallenged very frequently on social media.
Well, there not nationaltiy is discussed but MT.
If they do train for pure boxing, of course it is different question and boxer's origin doesn't have any impact on his skills.
Only talent and cocah, tutors, hard work etc plus conditioning etc.
I for example didn't defended universal superiority ideas about some linear TMA style because I had exp what is feeling to offer it to a kick boxer's apprentice that did had cross training in pure boxing. Sorry, yes, he wasn't able to headkick me or land uppercut or straight but hooks and half hooks…… wow…. If he wished, he easily was able to handle out very hard concussion.
Ok, later I was more realistic with KB guys of course.
Yes, karateka isn't a boxer….
Thai style muay thai has more in common with boxing than western styles of muay thai and kickboxing do.
About MT in Europe, I think it depends form coach/ trainers.
Some just know rules and are able to use elbows and knees, foot sweeps and clinch game due to another experience.
This doesn't mean that they even claim that they know MT, just compete under rules.
& Western kick boxing : in europe when becomed more popular, there plenty of TMA guys and boxers turned in KB guys.
Later in end of 90 ies some traditions developed but it depends.
Some gyms used also additional boxing coach etc.
# rules for ammies then were Low Kick, Full Contact, K-1 and some other stuff too, f.e Kick Light.
& Also there at least ammies had / have enough guys that competed in am KB and also in am boxing.
For example not rarity for Baltics or NL. BTW you may ask about this Lithuanian gentleman, instructor in your gym if I correctly understood from your post in another thread.
Greece and Cyprus too had guys with not bad hands.
Another way to check it is deep digging in amateur tournaments results tables, for example National championship and compare name/surname/year/ place in tournament results. At least medalists lists. Another kind of tournaments : regional tournaments, not rarerly international cups esp these between National and Continental level.
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One example cos then I was more connected with KB ammies than boxing ammies and know a bit euopean ammy KB kitchen.
# Some big boxing events undercards had some guys with amateur credentials higher in ammy KB than they had in ammy boxing. Yes, now they are pro boxers.
Old cards I don't have time to dig in, will not type form memory.