I think there are two problems, one yes wireless is 'bad' You can think.
1. Reliable
2. Cheap
3. Low power
Pick no more than two. Bluetooth was originally designed to be cheap and low power.
The other problem is networking is complicated, and then throwing device API's on top of that makes it very hard to get right. USB had lots of issues originally. And once you leave standard devices like, keyboards, mice, and mass storage devices it gets iffy real quick. (Go scan through the libUSB mailing list archives sometime)
1. Reliable 2. Cheap 3. Low power
Pick no more than two. Bluetooth was originally designed to be cheap and low power.
The other problem is networking is complicated, and then throwing device API's on top of that makes it very hard to get right. USB had lots of issues originally. And once you leave standard devices like, keyboards, mice, and mass storage devices it gets iffy real quick. (Go scan through the libUSB mailing list archives sometime)