I dont think it stress the transceiver in the camera, but its just they are of such a slow standards that transfer times are much higher then the actual recording times, so it take longer to transfer the 3 minute file than it took recording it.
If a camera have wifi i always have it on along with the screen too for my testing in relation to heat endurance, its a worst case scenario but as long as you can have the wifi on all the time and ditto LCD screen, then i test it cuz there are some that would do it though i personally see no reason to do so.
Newer cameras ( action ) do seem to support the faster 5.8GHZ bands, so things are moving in the right direction for sure.
This are one of the reasons i hope i get my hands on newer action cameras like the SJcam SJ8 pro that are claimed to support 802.11n.
I am not quite sure if it is the dashcam manufactures that go cheap and put in slow wifi modems, but i dont think that's the case.
No doubt things are getting smarter and smarter,and that's often not something i like, but at least as long as you can turn off the damn wifi i will be okay.