Besides, the common behavior is to do what it says on the tin by default, but offer flags to make cli's "simulate" their run with "--dry-run" or similar.
I'm not sure I know of any utility that would have the opposite behavior than that.
The "install -y" pattern is kind of similar. Various tools have as a default that it gives a list of packages that would be installed, and then ask for confirmation.
A "Hey, this is really going to delete files. If you're just playing around here, maybe try it with the --dry-run flag" seems sane and (so long as it's asked for) means less syntax to have to know up front.
Arguendo, having to type extra characters to enable the functionality that the tool says it will do in its very name seems backwards to me.