I think it depends on what you want from the meal - there are lots of YouTube videos on Celebration at the Top, so I recommend you take a look. CG is going to be a 3-course prix fixe meal with a starter/entree/dessert, and although I like the food, IMO the restaurant tends to be very loud, and there are lots of kids (not a criticism of the kids, just a comparison since it's an anniversary meal). Celebration at the Top is a meal made of heavy hors d'ouvres, if that makes sense - upscale sliders, sushi/sashimi, shrimp, salmon, ravioli, bao (sounds like they have changed this to pork katsu sandwiches?) etc, and then a dessert buffet. I thought the quality was really good - the desserts aren't the typical meh dessert party stuff, for instance. And there is one price for adults and kids, so it tends to be more adults. The rooms aren't as pretty as the restaurant, though, and you may need to arrive early to get a table by the window.
See what I mean? It just depends what you want from the dinner.
For me, I think Celebration is one of the best "extras" money can buy for adults - pricing includes adult beverages (not just wine - anything), and they are not stingy. Plus, you know you will already be at the restaurant when fireworks start, no stressing about someone loitering at a table and messing up your seating time. Let me put it this way - I have a solo trip coming up, and they just released a date on the Sunday I arrive, but I land at 5:55 pm. I so loved the one I did that I am tempted to book it and switch my flight to arrive on Saturday!!!! I'll be at WDW with DH in 2025, and I am going to book us one of these...