Elysium player here, made an account just to affirm that the lag has grown significantly when bossing in a party of 4-6 members.
My first registered mention of this lag is on Saturday March the 28th, 2020. My bossing squad clears hLucid and hWill in matter of minutes, usually with zero or one deaths, but with this lag some people get close to dying out due to being frozen for 10 to 20 seconds at a time.
Skills can't get cast, bosses freeze, desyncs happen between party members (one member registered Lucid's lasers, the other member registered Lucid's clockwise touch attack); it has basically made endgame bossing in Elysium near impossible.
