I'm in almost the exact situation. Main flock 2.5 years old, a couple other reliable layers ~that age or slightly older. And 4 pullets almost 9 months old, barely an egg a week if that.
An older hen started molting early Sept, everyone followed and fully feathered again, but still not laying.
I have health issues and we pay kiddo allowance to feed/water/open close the coop door and she's tired of it. I too wonder if it's worth it at this point. She's not happy going out in super duper cold windchills in the winter and I don't blame her.