After install the first time I opened adobe it opened quickly and normal.  Every time after that opening adobe was painfully slow.  Here is the regedit key I changed and it now open quickly.

\\HKEY_CURRENT_USER\Software\Adobe\Acrobat Reader\DC\Privileged

Name of the key is”bProtectedMode”
1= Enabled
0= Disabled

References:

https://forums.adobe.com/thread/839984