BA of course are self interested. "It's not our fault" is an easy way out for an airline whose performance is slipping visibly. But in this case the lack of staff at Heathrow for security and baggage has been a disgrace for the last couple of years based on my direct experience. And for the length of stay anyone from here is likely to have in Britain, you cannot just rely on the limited amount of cabin baggage now allowed. You are going to be staring at that carousel for a long time while the same "priority" tags go past again and again. And on the way out you will be in a line up that strangles the rest of the terminal outside the "quarantined" area. One good feature of this is that it is surprisingly easy to queue jump - because no-one actually knows where the back end of the line is, and they have to keep opening up the tapes to allow for legitimate cross traffic.
And there is also another piece in the same paper
No longer is an airport a gateway, but a stopover destination in itself, a hell where the suspension of your human rights must be endured unquestioningly, even gratefully.