The tutorial does have a lot of useful info but it's still a giant wall of text that they hurl at you and you will forget stuff 5 minutes later without reinforcement.
Like the tutorial explains increased/more modifiers as well as explicit/implicit item rolls which are both very crucial aspects of PoE character progression. However, if you skimmed over it then you won't really get how important these are.
Probably the other big hurdle is how much PoE changes within a single year. All those Atlas mechanics tutorials are going to be dumpstered in a month when we have a new Atlas. I can't even imagine the headache content creators going to go through scrapping all of their videos for PoE 2.
I also think that the extremely open ended nature of PoE makes it difficult to even get fundamental build making aspects.
Example: Most builds in PoE use a main skill, a movement skill, aura/curse skills, defensive skills (CWDT Steelskin etc) and support skills (totems, golems). However, a new player has no idea that these should be considered into builds so they are instead going around with 4 4 links in their build all of which act as main damage skills. They don't know that you are allowed to have one totem and one curse for free.
Another thing is that because of Diablo 3, a lot of new players fall into the trap of going too hard for main stats (Intelligence/Strength/Dex). These are all issues that are hard to solve without more deliberate direction by PoE.
Another basic primer on PoE: