For me every completion list for every member access contains preventFreeze() and makeShared only because one of my dependencies (not me) uses ktor. I ofter use a completion list for observing members and seeing these two function every time is quite annoying. I personally think that having such extension functions on primitive type is a pretty bad practice since it pollutes everyone. If you have such dangerous API that shouldn't be normally used, probably it's better to define them as global functions without receiver.
To be honest, I would be very interested to know the reasoning behind the decision about making such functions, since if every kotlin library would add two extension functions to Any it would be probably nightmare. Also I'm wondering is any chance that these two functions would be removed from the completion list of every member access in future updates?