Yeah I'd say 6-7 months. My eldest played with it sat up but was more interested in other toys so we got rid. But as @Lauren has said, my 2yo is now playing with it now it's back out.
I put my baby gym away about a week ago (baby is just over 5 months old) as everytime I put my baby on it she just rolled over 😅
My nearly three year old has started playing with it again while it’s been back out for the baby! 😂 but seriously they tend to lose interest once they’re sitting up and moving about more so they can play with other things, so around 6 months would be fine to pack it away.