MacOS Bluetooth Appears "Permanently" Not Available? (MacOS 10.15 Catalina)
macOS Catalina Version 10.15.6 (19G73) seems to have &quot;fixed&quot; some of the problem but not all of it...
The MacOS &quot;Console&quot; System Log still has some error messages however the bluetooth connection does show up in networking.
bluetoothhd : deny(1) mach-lookup com.apple.server.bluetooth
Here is what the screen shot of the system log files look like if you search for &quot;bluetooth&quot;

the suspicion is that this is a hardware to OS &quot;bridge bug&quot; that is specific to MacBook Pro's?  For example... my system with...
Hardware Overview:

  Model Name:   MacBook Pro
  Model Identifier: MacBookPro11,3
  Processor Name:   Quad-Core Intel Core i7
  Processor Speed:  2.8 GHz
  Number of Processors: 1
  Total Number of Cores:    4
  L2 Cache (per Core):  256 KB
  L3 Cache: 6 MB
  Hyper-Threading Technology:   Enabled
  Memory:   16 GB
  Boot ROM Version: 162.0.0.0.0
  SMC Version (system): 2.19f12