Yes, it's true. My dogs would always meet people new to my home with their tails wagging but cats are different creatures - they meet people on their own time and are troubled by strangers in the house, just like BL said in another thread. I just snapped this photo of Shiloh upstairs. My grandchildren are wonderful gentle kids but Sweet Babycakes is still not "all-happy" with people in my house beyond the old numbnuts, my wife, and my son.
Cats are strange creatures but their instincts have kept them breeding for many hundreds of thousands of years.