when dealing with retrieving a large followers list from API, what i did was estimate the no. of pages i need (total / 5000) from the follower count of user's profile, and then send concurrent API requests to improve the speed.
now with the new cursor-based pagination, this become impossible(it stills work, but i guess page-based pagination will be obsoleted someday?), because I don't know the next_cursor until I finish downloading a whole page. so i guess the page-based should be preserved (and improve)? rather than making it obsolete?