I would add:

- natalism. Some people worry about inverted demographic pyramids. They want to see more births, so they need more horny guys trying to form relationships instead of being content single. Sometimes there is a racist angle.

- industry. Anything that's "too fun" for young people disincentives education or working.

- addiction. (But people get addicted to shopping or eating dirt too.)

Some arguments against outlawing it include:

- free speech.

- a sizeable fraction of the population wants it to exist.

- better option for economically impoverished women than prostitution.

- societies that suppress it don't really seem better for women, or anyone.

- prohibition of a widely demanded product creates crime (and nothing is easier to smuggle than pure information).