I’ve gotten this question a couple times. It’s both, and it’s more. Other topics I’ve seen it happen with: sex magic and love magic; curses; weather magic and other magic that some believe isn’t possible; invading dreams or hag riding; etc.
The problem is more of Tumblr’s approach to witchcraft than it is with actual witchcraft. Witchcraft has no morals. Religion has morals. People have morals. On Tumblr, people make morals into strictly enforced rules. Combine this with the “No one is allowed to make a mistake” policing on this site, and the hypocrisy can lead to some really confused and disheartened beginner witches. Imagine being told you can do anything, do something, and then later receive backlash on Tumblr because you’re a “horrible person” for doing it.
This also gets tricky because there are millions of practitioners on Tumblr with millions of different paths and beliefs, so gathering you sources from many Tumblr posts can lead to contradictions. This is why I suggest people to not learn witchcraft from Tumblr alone (if they’re just starting out).
Everyone’s allowed to have morals. If you’re teaching witchcraft, though, be honest with yourself and others on what you believe can and can’t be done. And remember no one’s obligated to follow your rules.