I wholeheartedly believe there's nothing more important than ensuring everyone has the security, access, and privilege to enjoy a nice day in a park with friends.

There is, in my mind, very few things as important as enabling that in a sustainable and equitable way. Everything else is just supporting that, people enjoying life without needing to worry about anything else in that moment.

Just to emphasize, some of the things we need to get to a world where everyone can have that:
Equitable housing
Well designed cities
Get a handle on climate change
World peace
Fair wages and working hours
etc

But that should be the goal in the long run imo. Enabling people to live life.