Why does using parental controls mean that you can't also educate your children about good practices on the internet?
It doesn’t? Literally everyone here is saying that you should do both. No one is saying that using parental controls is bad. They’re saying it is insufficient to solve the problem.
Why the assumption that anyone who does blindly trusts them and doesn't attempt any other form of education?
There was no assumption here. Most of the thread is saying you should be a present parent and do both. I think if you are blindly trusting tools, you’re going to have a bad time. Further, if you want to shift your story to be that you do both education and parental controls, cool. So far you’ve said that you prefer using parental controls than “arguing with your kids every 10 minutes.” Regardless, you can do whatever you want as a parent.
I don't understand this religious adherence to not using the tools that are available.
I don’t understand why you at all think that anyone is “religious” about not using parental controls. I’m actually wondering if you are reading the responses. Literally no one is saying “don’t use parental controls.” No one in this thread is suggesting what you are saying here. Again, they are suggesting that parental controls are insufficient and cannot make up for being a present parent. This is not hard to comprehend.