I had a look and it seems to be true! Thank you!

_That said_, their "Discover" range of videos on youtube sure look like ads (albeit not banner ads). I know that Tesla have had a presence at a bunch of EV events here in Scotland; they have a stall and cars there that you can test drive. It's definitely not banner-ad-on-google, (and the publicity from stating they don't do ads is likely an ad in itself), but it's definitely "paid marketing"

Super interesting though, thank you for giving me a rabbit hole to go down!