I've been seeing more and more references that the British Celts aren't even considered as "Celts" anymore because of culture differences between the mainland Celts. Are these sources to be trusted, meaning everything written in the history books is to be false? I'd like to know if any Celtic history buffs agree with all of the British Isles hype that's been going around lately, because it could change the game dramatically.

Personally I find it ridiculous that the Celts of the British Isles are to be excluded from the culture because of a few recent studies from seemingly hateful sources.