[chiv]

why doesn't the latest 16.0 kodi version support many of the add-ons ?

[learningit]

why doesn't the latest 16.0 kodi version support many of the add-ons ?

How about some details (which add-ons) and a debug log. No one here is a mind reader.

[3CupsOfCoffee]

Kodi 16.0 right now is a "Release Candidate" not the final release. They are working out the bugs.
Addons might not be updated for 16.0 until final (Stable) release.
The average user should stick with stable releases. (15.2 is latest)