I quit carrying one 20 years ago and have never missed it.
If you're around cops and need one, you'll be deafened by the clack-clack of tactical stabbers being flipped open.
If I'm at home, there are knives around.
I have one in my whip.
The closest I've come to actually needing one was at the post office (where knives over 2.5 inches are just as illegal as .44 Magnums, by the way) and needed to open an over-wrapped package. Luckily my ride is old enough to enough to have an actual key, which worked fine for jabbing tape.
I have no idea how many I lost before I just gave up. The last time I remember actually having one I was picking up my oldest kid from grade school. He's 30 now. My state of the art Spyderco was clipped in my front pocket, and a kid waiting to get some kind of comeuppance from the Principal pointed at it and said: YOU CAN"T HAVE THAT IN HERE. I was also carrying a .45 automatic. I just said, you're right kid.