Supply and demand, along with historic sexism.

• teaching (up to high school) has historically been predominantly women. And yes women used to be paid much less. That gap has narrowed a lot but “women’s work” still tends to pay less
• there are hundreds of thousands of teachers. There are huge numbers. There’s always another
• while it takes a lot to be a good teacher, it’s not so much to “teach”

So I think we have a history of low pay, the vast number militants against that changing, and to appearance anyone can be a “teacher”

Don’t get me wrong my family has significant history in the field and deep respect for the importance and to the huge impact a good teacher can make on someone’s future. But when my kid wanted to teach, after saying I would be so proud as would the vast array of ancestors, I added that you need to be aware of poor pay. To translate to video game, it’s doing life in hard mode