Technically you’re right as we lost two rides and gained two back, coming out to equal.
However, Snow White (~600) and 20K (~1200) were not necessarily putting people through at lightning speed. Meanwhile, Mermaid (~1800-2000) is one of the highest capacity in the park and 7DMT(~1500) both easily beat out both older rides and that's not even including Enchanted Tales (~300) and Be Our Guest, which seats to capacity daily usually. Then there's just expanded pathways which was needed, but also, and most overlooked, Dumbo doubled it's hourly capacity from 600 to 1200 if both Dumbo's are running.
Snow White and 20K's total capacity comes out to only around 1800 combined. Let's say ~2200 on a busy day maybe. Fantasyland - with the same number of rides as before - now has a capacity of ~4400 at minimum between 7DMT, Mermaid, Enchanted Tales, and the added second Dumbo. I wouldn't know how to calculate Be Our Guest in, but it has 546 tables (So if the restaurant is filled, that means we're talking at least probably 1500 or so i'd say in the restaurant at a time if you say go by an average of 3 per table. It could be closer to 2000 if the realistic average is around 4. I don't know how fast the turnover is between parties or should I say how many reservations they book per day would probably be the more interesting thing.
So if you add in 1500 at minimum from BOG, then that brings the new total to ~5900. And I didn't even factor in Princess Fairy Tale Hall, which is fair game since it's not a new build and uses the Snow White attraction spot, which would push to total over 6000. Remember, utilizing the same land that all of this stuff is on, SW and 20K still only add up to around ~2200 at best. New Fantasyland uses space more efficiently (in the NFE area) which is the reason for this. 20K took up an obnoxious amount of space. The bad thing to come from this all was Princess Fairytale Hall taking over Snow White instead of a new ride (although it is a small building).