David’s definitely a Monzo lover though. Have you seen the video of him interviewing Tom a couple of years ago? Not a screaming school girl but does seem in total awe of Tom, and why wouldn’t you be if your passion is fintech and you are interviewing a fintech rock star? 
I think he gets a lot of feedback that Monzo is mentioned too much and everyone has only positive things to say on the show, so he must be under a lot of pressure to balance things out with negatives and try not to mention them too often.
Monzo is still mentioned on every single episode though (whether the piece is about them or not), so you can understand why people who aren’t Monzo lovers would get annoyed by it, but having listened to every episode I personally think there is no general bias due to Jason Bates’ involvement (other than Jason’s own - which he tries hard to avoid but can’t). People just have a lot of positive things to say about Monzo.