At a milonga, it’s a good idea to take the time to dance with beginners. You might not end up doing much more than walking and basic stuff, but that’s okay. Chances are they’ll appreciate the time you spend with them, and your patience is beneficial to their learning.
But there’s more to reaching out to beginners than just helping them improve their technique.
It sends a simple but strong message: Somebody cares.
A tango community with lots of people like that has the best chance of growing, and always seems more memorable than one that merely aspires to include good dancers.