there’s no need for the apostrophe

Ok, I fixed the typo.

There’s a difference between “a beginner” and “someone who is very experienced but hasn’t done X”.

If they haven't done X then they are a beginner at doing X - no difference - this is in fact the target audience for many tutorials. The other things which aren't covered in the tutorial you put in the pre-requisites.

not a “developer who understands and uses 90% of the same tech stack, but is looking to do something new related to it”

and yet, a lot of tutorials written for developers who have used 90% of it are written just as badly, hence the huge upvotes.

If it were aimed at true beginners it would be written completely differently

That's the point! Many tutorials need to be written completely differently! 😂 For starters all of the ones at Microsoft.

A university teacher preparing a lecture about shakespeare doesn’t write the same lecture if their audience is a bunch of 5 year olds

That's because the course has pre-requisites that you must have passed before you can enrol in that course - if you don't, then you have to go study those things before you'll be allowed to enrol - and they are explicitly spelt out in the guide to enrolling, hence the professor can write the lecture safe in the knowledge that all students in his class have completed all of the necessary pre-requisites.

You know that’s not true, right?

I know it's absolutely true. Even my threads on Maths are written with the assumption that the reader doesn't know all of the background knowledge (in fact are written quite intentionally for those who are being bullied by gaslighters, and they lack the proof to debunk them).