Should I defoliate the middle?

I don’t know if I should defoliate the middle section. Is bushy and leaf tucking is becoming hard. She is just about hitting the stretching phase anytime now. And I want to let light and air in the middle section. But now leaf and stems are touching each other. I should have gotten a scrog net, but next run I will add that. Any tips is appreciated

Wait until after stretching has stopped.
Usually around the 3 week into flower.

It depends on conditions, but I have found its almost always a good idea to hollow out the middle for the airflow.
I have lost most of the yield on 8 footers because mildew started in the middle and took over the plant.
That was outdoor in New England with our lovely humid fall weather.

I think the responses you get will be varied based on personal preference. I defoliate all through veg and to about mid flower. My end results don’t suffer from it.