In the sense that "Brexit means N26 needs to now file a lot of license paperwork that wasn't necessary under EU law," yes.
If they believed their business would make them money in the UK, filing paperwork wouldn't be an issue.
Exactly. And it may have made them money outside of a Brexit context, and the calculus has changed post-Brexit.
This was the failure mode people opposing Brexit anticipated.
Making money isn’t enough, there’s also opportunity cost for not just money but finite administrative attention. For the same burden they could be pursuing a much larger EU market.