First file doesn't actually guarantee success when the use of the non-filer GREATLY exceeds the use of the filer. The purpose of trademarks is to prevent customer confusion, and courts frequently go by that, rather than technicality. A first-file rule basically covers what happens if two same-sized entities had the dispute -- it's either first file, or first use.

It's a whole other matter when, to 99% of people, "bitcoin" has a specific meaning, and this guy is claiming, "Oh, but my 1% of customers are the ones who are right." The purpose of a trademark is so that you can't walk into, say, a car dealership, ask about an Impala, and be sold something made by Volvo instead of Chevy. (And if I just fucked up the brand reference, pardon -- I know little about cars, I can't actually drive because of a vision defect.)

He may have filed first, but thousands of people were using the term already. Even if he was first, thousands of people compared to him and one fictitious client ...