Not much is closed. If you paid a ticket to go to HS 2-3 years ago, not much is closed from then.
I will say though that imo HS does lack. I'm ready for both new lands to open so wife and I have more to do. We don't go on Star Tours, she doesn't like ToT or RnR.. So for us, HS is like a 3 hour park. We go there because we're AP's. But that's no different for me than it was 2 years ago. It's not like half the park is closed. Attraction wise lights motors action (which I loved), and the backlot tour (which I loved also) are the only things closed. GMR is closing soon, so that's 3 things. So 2 years ago we'd still only spend a few hours there.
But like some people have said, they can spend all day there. And now we really enjoy going at night to see the star wars projections/fireworks
So if a couple years ago you spent a full day there, then really no reason not to do the same. If you're more like me and only spend a few hours there and you don't have park hoppers, then I'd skip it