I don't think this is necessarily a bad thing on its own - it's actually quite reasonable that one person's focus when "building a text editor" is going to be lower level along the lines of "how do I write a buffer and process key presses" while another person's focus might be "how do I embed a text editor in my app so I can add my own UI around it".

But it probably does warrant some kind of rating or explanation for each tutorial, especially for the less experienced developer.