Ok so lemme ask if i have the same score in career overall leaderboards as somebody else that has the same total as me, but they are 100 levels higher than i am. For example. Im prestige 10 lvl 46 4,803,290 total xp and looking at somebody a few slots ahead of me that is mp147 with 4,803,435 total exp. So they have 125 more xp than i have. That shouldnt make a difference in that many levels?
It depends on other factors as well such as thier score per minute.
I don't think the leaderboards are entierly XP driven.
The leader boards are different for each game mode i don't think they are accurate i don't fully understand them myself i think career is based on total points and spm which is mind boggling considering the top(1st spot) is getting 45000 spm.
And if you toggle few a few different modes looking at the top 10 you can see that someone is not playing fair or the entire list is just garbage made up.