It can be a lot of data the client has to fetch depending on how many people you follow and how many people they are following.

That being said nostr:npub10r8xl2njyepcw2zwv3a6dyufj4e4ajx86hz6v4ehu4gnpupxxp7stjt2p8 could absolutely cache and calculate a subset of that data and only do a API request when the user wants to see the full WoT or if the selected subset is unlucky and shows a WoT of 0.