Athens and to a lesser extent Milan (ex-LTN but Wizzair base and previously applied for slots MXP-LGW) are just BA dumping low cost capacity into Wizzair markets. I’d imagine they’ll survive as long as Wizzair keeps the routes open.
I’d be interested to see if BA start LGW-BKK. They’ve just canned LHR-BKK for Summer 22. Now Scoot have entered the market it would be not unlike BA to try to squeeze out low cost competition. They’d also be able to use the moving of low yielding O&D long haul routes as pawns in their fees dispute with Heathrow.