I'm sure the experience was inconvenient for those on board, but realistically we have no idea about the drivers wellbeing or reasons for doing what they have done.

In terms of not telling the passengers, if the driver was in a bad place then the last thing that's going to help is to tell a bus full of passengers that they aren't getting home (even if there is a mechanical issue which means the bus physically cannot move, passengers still moan!), so I imagine they've decided the best option is to avoid any conflict at all?

From my point of view, if reports are true and the driver wasn't in a great state mentally, then they've absolutely done the right thing in not continuing to drive which would have potentially put themselves, the passengers, and other road users at risk. Given that the passengers have went straight to the press I think the driver has also made the correct call in not telling them why, as it doesn't seem like they're the most compassionate bunch. As for them being "helpless" as per the BBC article - there's literally an emergency exit at the back of the bus, and the front doors will have had emergency stickers instructing to push/pull on them as well as emergency buttons nearby.

Obviously we don't know the specifics and I doubt we ever will, but I'd hope that the driver is getting support if required.