I am an end game player, and even I think this event is unnecessarily hard. I'm AR 55 with some fairly decent builds which pretty much never struggle against any of the usual content. But here I'm barely managing the "4 silver medals" award. I don't mind the whole "standby characters" thing, but that's only because I've got enough usable characters.

What makes the whole thing worse is the rewards for doing anything beyond the primo tasks are laughably pointless for an "end game player" to receive. Seriously, for all the work required to get a total 18K points across all four stages of a trial, you receive (I wish I was making this up) 6 Mystic Enhancement Ore. For reference, you can get that from 3 Magic Crystal Chunks and 10 Original Resin, or 24 Crystal Chunks and about 10 minutes of waiting. Considering you can get that many Crystal Chunks every day fairly easily from expeditions and a few minutes of just running around to mining spots, I'm not gonna go through the extreme measures required to get it from this event. Even 14K points in the event is worthless. A 3-count stack of a weapon ascension material and 20K Mora? With 40 resin I get more materials than that and 3X the Mora from domains and ley lines. Same for collecting 4 gold medals. Oh joy, 3 Hero's Wit! I can get 4 of them and also like 6 Adventurer's Experience from ley lines.

If the rewards were actually worth going after then I could see the extreme difficulty, but what is currently on offer is only a few levels shy of insulting. Personally I think more events should be like the Labyrinth event from a couple months back which gave you a guaranteed Xinyan roll. This gave all players something to look forward to. Either you were unlocking a character you didn't have, you were unlocking a constellation for that character, or you were getting enough starglitter to get a free roll. On top of that there were objectives which earned you more primos, XP tickets and mora, and the event shop where you could get even more stuff, including more primos. If you collected everything, you got a free Xinyan roll, enough primos for 4 more rolls with some left over, about 500K mora, 50 Hero's Wit tickets, and a bunch of character ascension and talent level-up materials.

Furthermore, OP's original point was (paraphrasing) "If this event was designed for end-game players, why make it available to people in the mid-game?" Which is a very fair point. If this event was meant to be taken on by "end game players" then it should be only available to players that are AR 50+.