Roman Abramovich bought Chelsea in 2003 for £ 140M.
Todd Boehly bought it
from her majesty's trustees in 2022 for £ 4,250M.
That was a compound annual growth rate of 19.7%
, sustained for two decades. That's "Mitt Romney's 401k" levels of returns.
Even if you only credit the valuation of the club at the £ 2.5B that Abramovich would have received, and back out the £ 1.75Bn in promised investments in the club (which you'd think would increase its enterprise value by an equivalent-or-greater amount), that CAGR is still 16.4%
Compared to those returns, you can sustain some negative cashflow for a while.
And the new investors will probably have an IPO as an exit option, with the inflated valuations that would entail given that it would essentially be a meme stock.