Why does adguard need https filtering & pihole doesn't, & for what

[batman]

I understand that pihole is a dns adblocked, which means it doesn't need to deal with http/https stuff, but I was under the impression that adguard is the same, a dns blocker, but here What is HTTPS filtering | AdGuard Knowledge Base it says

Why does AdGuard need to be able to filter HTTPS?​

Most websites are now using HTTPS, and the same applies to advertising. Here are a few popular websites where you can’t remove ads without HTTPS filtering: youtube.com, facebook.com, and twitter.com.

does this mean, pihole can't block youtube/facebook/twitter, ... etc ads at all, & does this mean that adguard home process the pages's code similar to blockers like ublock origin, or am I missing something, & regarding their dns functionality, does pihole offer anything beyond what adguard offers in addition the to https filtering it offers?

[Bucking_Horn]

Pi-hole as well as Adguard Home are DNS servers, i.e. they only ever see DNS traffic.

AFAIAAO, Adguard offers at least three different kinds of software: a browser extension to be installed in each browser you want filtered, a standalone application to be installed on each client machine, and its Adguard Home server solution to be installed on a server in your network.

As far as I can tell, the HTTPS filtering feature you relate to is available in the Adguard application.