I know that I have an accent because my children spell some words phonetically (“discusting” rather than disgusting, “evulution” rather than evolution).
There’s nothing wrong with an accent as long as it is easy to understand. I remember watching a TV show (I think it was called Canny Coppers) and the accents were so strong loads of it was subtitled.
People shy away from talking about regional accents (because it’s awkward and uncomfortable - no one wants to be Hyancinth Bucket). Letting children think that having a difficult to understand accent is fine (and that anyone who struggles to understand is a snobby, plummy ponce) lets poor children down. Middle class children (even if they have an obvious accent) will generally be easy to understand.
Try presenting something to some Germans or Swedes (or anyone straight talking for whom English is a second or third language). The ones I know are baffled by our inverted snobbery around accents.