They are great for people who seriously want privacy but I don't think most of us want to have serious privacy for our transactions.

In investment aspect, I don't like privacy coins because they are most favorite targets of governments. There will be more regulations on privacy coins as well as more fud against those coins. If you are investor, you don't need it.

If governments launch more regulations, enforce exchanges to delete privacy coins, exchanges will have to do it. Price will react very bad with delisting news.