edit: to be clear, if companies are committing fraud in their marketing, that should be prosecuted or if regulations around misleading marketing are weak, that should be legislated of course.
What would you rather have? More regulated gambling and less addicts, or unregulated gambling and more addicts? Personally, I prefer the former.
Honestly, calling it "personal responsibility" when a powerful group is actively working to exploit that flaw seems a little weird. But even accepting that, we outlaw plenty of things because we think society isn't currently responsible enough to handle them.
That's why you see so many college boy on their marketing video.
It's completely fine when you're old enough to be responsible, and to know that gambling is a degenerate behavior that you can allow yourself sometimes to release the steam, but these companies don't make money from us.
They make money from the kids overspending because they are convinced they are going to get rich doing that. That's manipulation.
It would be like showing McDonald ads to starving African kids, of course they are going to make the wrong choice when offered food. They can't think rationally in that state.
Yes online gambling and sports management actions are their personal responsibility. And we should blame them for harm they knowingly cause.