No, the point of DOH is that you don't have to trust your ISP. In many countries the ISPs are actively hostile[1]. You do have to trust the DOH provider, yes, but in this case Mozilla (or yourself if you have the tech knowledge) will be verifying trust on your behalf. You cannot do that at all with plain ol' DNS.
DOH is a "best of a bad situation" kind of solution, it's a reaction to hostile ISPs. It's not something anyone really likes.
DoH means handing your data to one more party since your ISP can already see your SNI headers and the IP addresses. The only thing DoH does is stopping DNS spoofing at the cost of handing your data to a third party.
> The only thing DoH does is stopping DNS spoofing at the cost of handing your data to a third party.
It sounds like you think that's not worth it, but the evidence is that others disagree. Personally, I see both the pros & cons and have no strong feelings either way. I trust Mozilla's evaluation of the pros & cons more than I trust my own so I'm happy to do whatever they think is best, and I suspect most users feel the same way. If you disagree with their evaluation, you can toggle it off in Preferences, and they even show a banner on first start-up giving you that option.
DOH is a "best of a bad situation" kind of solution, it's a reaction to hostile ISPs. It's not something anyone really likes.
[1] https://www.internetsociety.org/blog/2014/04/turkish-isps-hi...