As a former Barclays customer I can confirm this. Last year I changed from self-employed to limited company and changing my business account at Barclays proved to be impossible despite always previously being in credit with no issues at all. I was able to open a monzo business account in less than 20 minutes.

This, I should add, at a time when there was a high incidence of fraud with people trying to open business accounts for dormant and non-existent companies simply so they could claim Govt backed loans where it was clear that very few checks were actually being carried out.