The honest answer
Ableton Push is worth it if it changes your behaviour inside Live. If you start ideas faster, record more expressive drums, launch scenes instead of looping forever and automate device macros more naturally, Push can be a serious workflow upgrade.
It is not worth it if you mainly arrange with a mouse, use third-party plugins that need screen attention, or already finish tracks comfortably with a compact MIDI keyboard. Push is not a shortcut to better taste. It is a better physical route into Ableton Live.