Instantly, as the club would probably retain its value in the very short-term and probably grow in value in the long term.
The club would be a valuable asset on an owner's spreadsheet. Plus they could take money out of the club if they wanted, year to year. Just because you've paid £2b cash, doesn't mean your net worth as a company or individual has gone down by £2b.
I would imagine there are, or will be, companies and people, perhaps with experience in sports entertainment, who see a London based club in the PL as a safe-haven to park their cash.
Whether they'd care about success on the pitch is another question.
Good points. But "people" have been saying the PL bubble will burst for a few years now and the TV revenue is already down on previous years. It feels a lot more risky with the money required (to buy a top 6 PL club), than say 5 years ago