Trump is certainly the most infantile of all American presidents and possibly the most infantile adult currently who wears a suit to work. Power infantilizes the dictator or dominator.

Consumerism is also an infantilizing force, which means we're all tempted to be infantile in various ways. I've written a few things specifically on Western infantilization, if you're interested.

https://medium.com/@benjamincain8/american-infantilization-and-the-age-of-reason-2da7faf92c34?sk=a76c121e43a5314438d12c81e04be822

https://medium.com/lotus-fruit/aladdins-lamp-and-the-infantile-consumer-c9aeae02fb77?source=friends_link&sk=55de3c09eb3aaf5287f786d495d5bb1a