Well... for a while yet. Depends on what else Elon and the gang might have on the drawing board.
When it’s needed, there’s no reason we couldn’t send out a robotic repair/refresh mission. It would not need to return.
If the instrument is still giving good data when the thruster fuel is running low, we could surely send out a fully-fueled thruster unit to attach to the sun side and prolong the mission.
I hope we develop the robotic capability to keep Hubble in the game too.