There has been no announcement from BA ,as yet , indicating they will scrap the route permanently.
they have already suspended domestic routes from Heathrow to Newcastle , Leeds, Inverness and there has been no suggestion they wouldn't return at some stage.Belfast has been taken off sale from 13-30Apr but seats are still on sale from 01May.This would suggest it's a temporary measure and the BBC NI reporter has misinterpreted the situation.
On the other hand , there are political sensitivities regarding the "National Carrier" ditching the link between N.I. and the UK capital. The last time BA pulled off Aldergrove to Heathrow was in the aftermath of the horrific events of 9/11. If BA did want to get off the route , the current situation with Corona would be an opportunity to do so with minimum political flack
we will have to await either official confirmation from BA or Belfast City Airport , or for the thoughts of an insider from either of these.