It's because of the maps. In terms of gameplay, silksong had the leg up. But compare each map to silksong. Hollow knight is far bigger. Hidden areas are very small and uninteresting as well such as the ducts. The only large areas in ss really are the castle area which feels bloated at times. The layout of hollow knight was also more interesting. In this game you start essentially at the bottom. In hollow knight you can explore up or down because you start in the middle. It was also far more rewarding to find a new area only because you gain a power up. The overall maps aren't as pretty as well and utilize pretty much the same color palette. Part of the reason for all this is because is more linear this includes quests such as the dumbest part of the game where you are forced to hunt spikes. There's also no comparison to the soundtracks