A thought. What determines what weapon and gear are displayed here? Is it just what was last equipped before the Splatfest finished? Someone could play normally, reach 4th place and then equip the H-3 to mess with people reading the display.
Valid point, in fact. The Splatfest lasted, say, 30 hours (close enough). Accounting for matchmaking time and being optimistic, that's not time for much more than 450 games in total. For a record like that after those games, taking into consideration the boost from "most turf inked per game", one would have to win 275, lose 175. But... that's not actually crazily unrealistic, is it? It's an 11:7 win:loss ratio, just 61% victories, which is nothing compared to what's required for S+99, 71%. In fact, with a 71% win ratio, you can get 100 more wins than losses in around 250 games. And there's nothing stopping two or more people from playing in rotation in order to maximise the time spent battling, other than the availability of two suitably-skilled players in the same location.