[eru]

If they can keep raising money from investors, that seems proof enough to me that the economics must be good enough.

Ie investors would only put up with losing money (and keep putting up money), if they are fairly convinced that the long run looks pretty rosy.

Given that we know that SpaceX can tap enough capital, the uglier the present day cashflow, the rosier the future must look like (so that the investors still like them, which we know they do).