Yes, I mean, that’s also a possibility - or someone didn’t know they needed to screw on the antenna, or it’s otherwise borked. Every PC motherboard (sample size of four, three for me and one for a nephew) I’ve bought in the last five years has had on-board WiFi and Bluetooth though, so I’m curious to know, was that a deliberate choice?

(In thinking about it, it’s possible that the motherboards I bought did have non-wireless alternatives that weren’t stocked at my local Micro Center - lot of digging required to figure that out, though :) )

Wifi is becoming more common on desktop motherboards, but it's still not a guarantee, especially on the lower end. On the higher end they can throw in wifi to make the feature list bigger without cutting into their margins. Out of my sample size of 4 over the past 5 years, only two had wifi. And honestly, I'd opt out of having that if I could trade that for a lower price or some other feature I'm missing, since I haven't used the wifi on those boards at all.