> Don't use doom etc, just standard emacs, otherwise you won't have any understanding of what is happening and how to fix it.

Doom and Spacemacs are IMO sufficiently good abstractions that you will almost never need to have understanding of the underlying system and to fix things. Sure for curiosity's sake you should still learn what's happening under the hood. But the abstraction is almost never leaky. I think everyone beginning Emacs should start with Doom or Spacemacs and optionally build their own config later on.