I've seen countless posts and comments on the fact that game modes like MDE or Refractrial is "too hard" or "centered around specific team building". Like yeah no shit? Endgame content is meant for players who are around the max level and having properly built ID's and ego's. Which is built up after spending hours getting through the main story of the game. You shouldn't expect to clear ENDGAME content fresh out the gate of canto 9 or even the intervallo.
I see people complaining about MDE hidden bosses being too hard, but isn't that the point? MDE is a whole is meant for players who have learned to build teams and push for certain ego gifts to properly clear 15 floors with adversities. I've also read "PJM hates solo players", like yea dude this game isn't built around soloing. The average player isn't going to solo all of MDE. That is what guides are for and where having endgame content levels of knowledge is applied. You should be able to deduce if the boss is worth doing or skipping based on your run (ego gifts and team you brought in). It is completely optional because of its difficulty too. The average joe is not meant to clear these with ease, especially with the insane buffs the respective ego gifts provide.
I also believe that having Refractrial centered around specific team comps being built isn't a big deal at all. AT ENDGAME, you should have a sufficient amount of IDs built and resources invested to pool together a required team comp. Especially after READING (oh so scary) the bosses gimmicks and figuring out that a lust team and gloom team is required. An endgame player doesn't need to worry about pooling those teams together because they are AT endgame. If you are not at endgame, don't expect an easy time clearing ENDGAME content.
TLDR; Endgame content means content for players at the "maximum level". It should be hard, but people are expecting cakewalks when they are clearly not at the endgame level for the endgame content. :(