I think it’s a good idea for tree-huggers to have small families. The big one is this: there will be fewer tree-huggers in 20 years, 40 years, 80 years. Smaller numbers mean fewer votes.
Over time, the zero-population growth proponents achieve their opponents’ goal for them. There are fewer of them. Meanwhile, people who believe in growth multiply.
People who believe that people are the ultimate resource do their best to increase this scarce resource. People who think that raw materials are the greatest resource die off. This leaves more raw materials for creative people who do not die off.
If you want ten more reasons for smaller families for tree-huggers, click the link. I recommend all ten . . . to tree-huggers.