I'm exactly that kind of moron. I've been tested by 23andMe, Ancestry, and Family Tree DNA. I've even submitted my raw data to GEDMATCH and market it as OK for law enforcement to use.
Why would I do that? Because several reasons.
First, I love the science and the hunt for clues.
Second, you don't have to be personally tested, to be located through DNA. Neither Golden State Killer and Bryan Kohberger had personally been tested by a DNA service. Law enforcement instead relied on tests done by relatives, even distant relatives, to narrow the suspect pool. Once they had a reasonable suspicion, they collected trash and did their own DNA tests to confirm their theories. If you think you can't be tracked through DNA because you've never been personally tested, you are sorely mistaken.
Third, scammers don't use DNA for scams. It's too expensive to use for this purpose. It's far easier to track and target you through other means, such as browser history.
So while it may seem scary to have your DNA results out there, it doesn't actually impact the ability of law enforcement or governments to locate you.