Trust it, no.

Is it better than nothing, yes.

Listen, some folks can afford to build and dedicate time and resources to making a pi-hole for their network.

Those who can't need to know there are alternatives, some are better than others, I'm just sharing information.

It's free for a limited number of queries per month. Generally enough for one device (depending on personal usage, obviously). Edit: It'll still function as DNS after that limit, you just won't get ad blocking and whatnot.

Mullvad has a free ad-blocking DNS you can use, too. I recommend the "base" version: https://mullvad.net/en/help/dns-over-https-and-dns-over-tls