'If someone has your bank account details, it increases the risk of fraud against you.'
This is actually an old chestnut, and not particularly true. Sorry to disagree. A fraudster can do very little, if nothing at all, with your bank account number and sortcode. The old Jeremy Clarkson bank story occurred many years ago, and before the introduction of the Payment Services Regulations 2009 which improved banking in the UK for consumers.
A fraudster can perform a lot of mischief with your debit card number and security details.
Do not confuse the two. Whilst it is correct procedure not to divulge your bank account number and sortcode willy-nilly, it is not particularly dangerous if these leak. On the other hand, guard your debit card details very carefully, as these are a payment instruction instrument.Guard Against Fraud