Celestial Park is huge, beautiful, and empty. It's a large expanse of stone, marble, and concrete without much to do besides the fine Carousel and some sit-down restaurants. To contrast, SNW has enough kinetics and energy built into the land itself, and is small-scale enough that if Mario and Donkey Kong M&G's were suddenly cut, the land would survive just fine. Celestial Park is the exact opposite imo.
The area is built for entertainment to fill the space and make it feel alive; without it, I worry Celestial will feel even more like a needlessly large liminal space that you are forced to trek between in order to see things you're actually interested in. It'll feel like the nu-Epcot Hub, with a Ruins aesthetic to sweeten that desolate feel. It needs benches, shade, and things to actually do; and that includes entertainment.