A) which premade config to choose
B) what half of those settings even do (and do you need them)
C) a lack of “sane” defaults that use the built in abilities
Realistically walking through the article authors “emacs from scratch” config and seeing what can be done with the built in packages and how is hugely instructive but even then you only get that from walking through the config one line at a time and reading “help” documentation for most of it.
At this point emacs is so old that fixing the problem of “sane defaults” is probably near impossible if only for how much it would break existing configs. But it might be a good addition to the tutorial to provide a set of questions and answers (possibly with demonstrations) that allow a new user to generate their own config with some nice defaults. We can assume these days that most new emacs users are coming from some other editors, so asking questions like “do you want auto complete suggestions in an inline drop down like VSCode” could be a perfectly reasonable question and then it could add the correct configuration settings to config for you using just the built in functionality
A small number of people with taste and experience.
Like one hopes to be the case for every opinionated preset profile set.