Have you even read the books?!
The books do indeed become increasingly dark. As evil forces gain strength, good people have to make hard choices, and some of them are killed for standing against those who would spread that evil.
Violent? Hardly. I’ve read Lord of the Rings – that was a violent series of books. I didn’t enjoy reading about literal heads rolling.
As far as being amoral, you couldn’t be further off the mark. They are incredibly moral stories. Each of the main good characters has flaws, and yet they consistently learn from mistakes and strive to make the hard choices. That seems like a pretty moral example to me.
Some of the “bad guys” experience remorse for their actions and change sides.
Oh, and the books take place in a co-ed boarding school, and there is never even the slightest hint that a single student is having sex! In fact, some critics are pretty hard on the series because of that.
Seriously, if you think the books are a portal to hell, then you obviously shouldn’t read them.
But mindless attacks that have nothing to do with these actual works of fiction do nothing to bolster your argument.