Talking to someone from Ford Europe Management in summer last year he told me that all these sales (Aston, Jaguar, Land Rover) have just one simple reason: Ford Motor Company is in big trouble and in urgent need of cash - so now they sell everything that generates money (AM, Land Rover) or try to get rid of everything that looses too much money (Jag). My bet is that Volvo is next on the table.
This has been widely publicised, and Ford have made it clear that this is the reason!
I guess as an American Company they can't be seen to be investing (ie throwing away) good money in Jag whilst the American arm of Ford is losing soooo much money. The revenue from the sales won't cover the losses for long, a few months probably, the bigger benefit is not having to put another billion or 2 into Jag!
Well as Volvo now becomes the only member of PAG then I'm sure they will be next to go, but will anyone want them?

Would the main manufacturers rather see them closed down?

Time will tell!
There is no doubting that in time to come that even as a minimum components (body panels, drive train, etc) for Jag and LR will be made at Indian plants, it remains to be seen if they would move production there, maybe for a larger volume Jag?