Well, now with Runeterra, and animated series, and "Project A" being dropped to the public by Riot today, their properties are probably going to hold that top spot from Fortnite for a while. At least, until their properties are separated by Twitch into the three separate games.
The medal objectives are just new versions of the daily quests function which has been a part of Fortnite for 4-5 seasons now. It’s definitely not new.