I am confused as to why "repair the thing before it catastrophically fails" is not the best of the available options. Decommissioning a facility like this is a loss for science globally, even if there are alternatives available. Telescope time is precious.
Spend time with your neighbors and local businesses. That goes a long way. Learn more about what works well in the city, and what doesn't. Consider serving in a volunteer capacity with various organizations like local neighborhood councils or schools. Most importantly, if you can devote time, money, or both to local schools, you will make the biggest impact there.
Have kids? Send your kids to the local public school. That is an enormous difference maker. Don't push for dumb things (e.g. Latin), but be an effective advocate for students whose parents might be unable to get involved, and contribute time and energy to improving resources across the board.
You can demand an end to "mandates" and public health emergencies, but you must then applaud when those things end.