But they are, for the buyer. More sellers = more liquidity. It just also turns out they (the sellers) are making money by picking up pennies in front of a steamroller.

I've been cynical about liquidity arguments in general too, but actually there's nothing to be sarcastic about here, that's precisely what they're doing. I've used Getaround to avoid having to own a car or go to a car rental office. Unfortunately for them, I don't need to do it more than a couple times a year because Uber/Lyft is more convenient and roughly the same cost.

At least if Getaround disappears, I'll be able to delete my Facebook account. For a long time they were only allowing Facebook or Google based logins.