It helps people know how many mods you have in your modpack so you don't spend time loading a modpack just for it to have too many mods and the game to crash. Having the number of mods would reduce the amount of frustration for the moments you have to choose a new pack just because the last one was too big because you didn't know the amount of mods it had.
I agree that this should get added.
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I think this will likely be covered by the planned update https://curseforge-ideas.overwolf.com/ideas/CF-I-495
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