I would probably mow now. I would try to identify any small trees that might be growing there first. With all the trees in the neighborhood, you might have a lot of tiny trees. If they used a lot of chemicals, you probably don’t have little trees. Just in my yard on the edge of town, I’ve had redbuds, mulberries, and a persimmon come up. I’m letting a couple of each grow. I had a lot of silver maples come up. They are one of the worst type of trees in the area. I pulled and tilled them.
I once saw our highway department spray and brush hog brush(young native trees), so they could plant pine trees. The pine trees all died. They don’t grow well here anyway, especially in compacted clay on the sides of the road. It was a long time ago. Hopefully, they are smarter now.