well I think the majority of parents closely guard their children when it comes to this issue (in a general sense), because children are very easily exploited, and this matter is one that's very easy for people to exploit others with, so they want to be fully in control or at least oversight of the teaching of this subject - the same goes for politics. Not always with great results of course, and sometimes unintentionally (or in the worst cases intentionally) harmfully, but mostly because of that protective impulse.

Generally, when parents talk about what they want their children to be, they say happy and prosperous, and something useful like a scientist or a bus driver or similar, or to follow in their own career sometimes. I've never heard a parent say they want their children to become pornographers. And again, the vast majority of parents don't want an authority figure and role model for their child to be one. I don't think this is because they don't want their children to grow up to not enjoy or engage in normal human interactions, but rather that its something that can (and often does) carry a great deal of risk and harm, and they want to wait for an appropriate time, when they're wiser, for them to experience or learn about it.

So I'm not sure your implied accusation (I hope I haven't misread you) that its reactionary to not want a pornographer teacher is true.