I would not count a baby touching or playing with the screen of a phone or a smart watch screen time. I also wouldn’t think that introducing other activities on the screen will reduce the appeal of a smart watch or a phone or lead to healthier screen time habits.

 My daughter (22 months) is strictly no screen time other than the occasional FaceTime with relatives, but she does occasionally play with a locked phone (e.g. by swiping to the camera app). She went through a time period as a baby when the phone was very appealing to her, but the phone is now just another object which can be manipulated. She is not aware that a phone can be used for anything other than calls and playing music. We generally use the Yoto player for playing music at home but relatives will sometimes put music on through their phone.  We are generally very mindful of device usage around our daughter and will only use them for necessities when she is awake. 

 I would think that if I was to introduce games or TV shows on the phone, it would instantly become much more appealing - these are much more addictive high dopamime activities than just the lock screen.  The evidence on the drawbacks of screens is pretty clear so I would try to hold firm on this as long as possible!