Earlier quoted context omitted.
They are using Brexit as a scapegoat. The referendum was almost 4 years ago and only last year they were talking about expanding in the UK. Some people might have been in denial but considering the political force of a referendum result and the glaring absence of any political alternative for years now, any other Brexit outcome was a fantasy and remaining in the single market never realistic. As you say the reality i…
I think you should follow UK politics more closely. Referendum was 4 years ago. But only until the recent election i.e. Dec 2019 did Johnson have the numbers in Parliament to actually "get Brexit done". And this week for the first time in 4 years, UK government is formerly advising businesses that there will be a hard Brexit: https://www.gov.uk/government/news/government-confirms-plans...
The point remains that this isn't the key reason behind their decision. I guess it's easier to blame Brexit than to explain to your customers that you're closing their accounts because of good old business.
They launched in the UK after the Brexit referendum and they don't even need that bank licence to offer electronic current accounts in the UK (Revolut did that for 3 years and their current bank licence is also an EU one so may also become useless in the UK).