The idea with all the developmental signs is that at the point at which they can sit up, pick up food, put it in their mouth, chew it and swallow, they're ready. Watching you eat is just like them watching your drive or use a knife, they're just interested in you, not ready to copy you.
They will take expressed milk on top of bm even when not hungry btw as they enjoy the ease of the sucking/swallowing compared to bm. It's a bit of a novelty.
Not satisfying him would show itself in other ways, not increased feeding which is normal at this age. His nappies would change, his happiness, his hydration levels, his weight gain etc.
They go through such massive changes at this age, go from little babies to sitting, rolling, crawling, chattering, interacting, giggling, interesting little people. And this takes calories. The most calorific thing you can offer them is milk.
I always say that it's easier to change what you're doing than the developmental norms of a little baby. So accept more help, sit on the sofa in an evening with things to hand, sleep as much as you need. Whatever makes it easier for you to ride it out.