Specifications are used to reference in conjunction with an implementation.
There are many specifications I could point to that would overwhelm most engineers yet they use those standards just fine.
Bluetooth is definitely not one of those "uses those standards just fine" cases... if a user has just a dozen peripherals, a even a 99% success rate starts failing on you pretty often
On a more personal note, I have to keep a mental map of which bluetooth devices will work with which bluetooth receivers... the tech is not NEARLY as universal as people like to think it is. Generally speaking, devices of the same vintage (or make) will talk to each other, but it is a crapshoot as to whether my a v2 headset will talk to a v4 USB receiver, or be seen by a new laptop/ipad/whatever.
The point I'm making is that it is a very complex standard whose use-case goes far beyond carrying audio from a device on a person to the headphones in his/her ears.
To give another example, GSM is also a very complicated standard (or more precisely, set of standards) but no one would really advocate for all landlines in buildings to be replaced with non-mobile GSM phones attached to the wall.
ISDN and SIP are complicated standards, but telecom engineers do advocate to their customers, whenever possible, to drop POTS in favour of VoIP softphone service run over the same lines.
VoIP-over-ISDN solutions are far easier to wire a large building for (it's just the existing ethernet drops, coming from the same switches the building already has, now carrying an additional VLAN); it removes many potential sources of interference; it increases voice quality; and it's just plain easier to deliver.
All that despite being, in pretty much every way, "more complicated."
