I read this article but it didn't explain much. Is the fact people like to cuddle pets with fur connected anyhow with our past when our ancestors had fur as well - and therefore could evolve an instict to enjoy hugging someone furry as an expression of friendship.
An answer I got from Jan Kolář of Charles University:
I'm not sure that people prefer fluffy things just from the fact that they are fluffy. They like things that are soft to touch such like pillows. The popularity of fluffy things might have a simple explanation: There's no danger of getting cut.
So the fact we like to cuddle with dogs and cats has probably nothing to do with our furry past.
It's sensorily similar to "why do people love to eat crunchy things?". Shops contain thousands of the most crispy foods. Crunchy foods and fluffy material like velvet have a common attribute. that they can both generate thousands of complex nerve responses. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1745-4603.1995.tb00782.x
Crispy foods generate nerve responses above 5KHz, and if you feel velvet with your fingers it has a similar effect. It's a kind of vibration, perhaps what they call vibrotactile.
Today they make haptic feedback with vibrotactile actuators, like a console gamepad, which is also designed to be pleasant.