If this is true, it's a welcome - and long overdue - move by BA.
I've never worn a mask when flying, and BA have been very understanding. No issues with cabin crew at any point, though I always have my exemption letter on my phone if needed.
Those who want to wear one still can, but to stop the safety theatre of the bien pensant dutifully wearing their masks, then removing them to eat and drink, will be a relief...