Somewhat tangential, but I think it's better to teach accessibility by examples ("screen readers will read this part," "an Alexa will speak it in this accent") rather than talking about HTML tags as if they represent some platonic ideal of semantics. The abstract stuff is hard to grasp, and it's often just wrong, e.g. when screen readers have bugs or don't implement certain things correctly. I like the author's example of "if you forget this, mobile users will have to zoom in which is annoying."