Degrowth is a shit name.
Everything we do grows us and everyone around us grows, growth is evolution and change.
You may be thinking of it as a critique of unsustainable population demands, but the word growth means so much more beyond that. We grow as people, we watch nature and loved ones grow, we grow fond of new things, just to name a few.
As for a better name, iunno anything that focuses on what you want to see, sustainabile populations or something?