They are a legitimate service. Whether you should use them or not is something you need to decide for yourself.
One of the biggest things they are good for is not giving all of your information away. A lot of these privacy companies simply spam out all of your information and request for the company to delete anything that matches that.
So for instance, if you signed up to a website newsletter with your email, they have your email address. And that's it. Then comes a "privacy" company that send them your email address, name, home address, etc and asks them if they have any of this data then they need to delete it. That's asinine and backwards.
DeleteMe doesn't do this. They are more specific with how they process the data removal requests.
I'm not advocating for them, I don't use them and probably never will. I have no idea if they are a good company or decent at what they claim to do. I just know they don't do the spam technique.
Personally, any company that is a mass sponsor of YouTube channels is something I won't trust myself. But that's just my weird litmus test.
while you're probably looking for some very tangible reasons in a bullet list of how its better, there's really one foundational reason and everything else is a distant second.
Linux (mint or otherwise) is your OS that you use on your hardware. Period. It's not going to tell you how to use it, what is allowed, what is right, or anything of that nature. It's yours. Have at it.