If you have a problem with people swearing in your comments, you can block the specific words you do not want to see. Go to the Youtube Creator studio, go to settings and select community. In this tab you will find a box called 'blocked words'. Fill in all the words you do not want in your comments and voila, no more swearing aloud in your comment section.
Also, I do not think Youtube will do anything to your comments when people swear in them. You're left to govern them yourself, hence why there is a feature that filters out spam comments and why it lets you block words.
I think it depends on your target audience. If your content attracts a lot of kids then definitely disable the swear words. I know as a parent I don't want my kids reading foul language and we make active choices on who they can watch (well we did when they were little).
If your content is more aimed at adults and you have no issues with the words then leave them.