0% APR is a unique scenario I think, as pointed out it makes sticking the capital in savings accounts a no-brainer. Under the normal run of things this calculus doesn't work.
0% APR wasn't available when I bought my M3P outright, and the Tesla of 2020 was different to the one now, end of quarter pushes weren't a thing (as far as I'm aware) and the price was the price.
I perhaps should have spent more time before ordering trying to understand the trajectory of the company, because whenever I've had a minor grumble about values cratering I've often condescendingly been told that Tesla's mission statement was always to get everyone in to EVs, therefore they were always going to crush resale values in the name of selling more cars. Had I known then what I know now, not least about FSD, etc - I would almost certainly have financed it if I had bought it at all.
I can't complain too much though because there's been plenty of people who bought at the real peaks of the prices, APRs and resale values - and had their pants pulled down big time on all three fronts.