Yes, of course, for people who have spent thousands of hours in a game learning absolutely nothing along the way and making no conscious effort to improve, everything above "dodge this 3 second telegraphed AoE" will feel like an insurmountable challenge. If the only measure of "success" one had during all that time was "clearing one way or another, even if dead on the floor for 80% of the fight", that's the player's own fault. Even normal content has lots of different mechanics that can be learned if anyone actually wants to learn. However, experience tell, that just dividing up into the alliance groups and having 4 people stand on the Atomos platform is too much to ask of players with triple digit clears of this dungeon.
A significant portion of the playerbase has used the fact that the normal content is tuned to be forgiving, as an excuse to not learn any mechanics ever. Alexander raids regularly wipe groups because expecting to learn which platform to pull the adds to, or when to turn into a gorilla, or how to freeze a tornado, is toxic elitism. Aetherochemical Research Facitilty features a 2 person enumeration tower. But why learn that, when you could just let the person explode? With current gear scaling most will survive with a sliver of health, or can be rezzed otherwise. Even dead healers are no problems, tanks at that level can solo. And since "completion" is the only quality measure, there is no difference. Same for the Eden raids, just let the enumerations explode, sacrifice some dps instead of soaking their tether. Just heal and rezz through it, never learn.
Dun Scaith? Who even knows how to do the mechanics there?! I mean, why bother, someone will do them and rezz. Burst the boss' shield down so that it stops critting the tank? Actually healing the tank? Why, someone else will do it (hopefully).
That's why Bozja is no different, more on that below.
It's not savage level, it's EX, for the very reasons I outlined earlier. Even the body checks aren't hard body checks, 1 or 2 failed towers can be survived. What they aren't though, is trivial content where a few higher skilled players can carry the majority of slackers like in normal content. And that normal content includes CLL, DR and Dalriada as well (I haven't done BA, so I cannot judge it's difficulty).
Bozja is not "midcore". A group of 4 semi competent people can clear every CE while 20 others lie dead on the floor. There is nothing "midcore" about it. The reason Red Choctober wipes so many groups so often, is because at some point, you don't even have 4 semi competent people in the whole instance anymore, or even 1. All the "midcores" repeatedly die to Red Choctober the same way all the "casuals" repeatedly die to it, by not ever having bothered to actually learn the fight. And that fight has exactly 3 mechanics. 3! Repeating! Mechanics! The same is true for the raids inside them. The bosses required "coordination" which amounts to "please split into two groups, a bit more dps and people bottom please". That's a laughable level. And even then, the main difficulty becomes "stop dpsing please". And even then, you have 3 minutes after one boss is dead to pick up the slack. 3 minutes! That's 2 whole burst windows!
You say that people can be carried in DRS. But the same is true for the Chaotic Alliance Raid. It's just that only a few people can be carried, you cannot have a majority be the one wanting to be carried all the time! As far as I am aware, that is also true for DRS.
"personal responsibility mechanics" - Yeah, good, welcome to adulthood. Stop being a slacker expecting a carriage. In Bozja, one can soak a single lane, or 3-5 (depending on class / loadout). The more each individual applies themselves to soak the damage, the less the armor is damaged, allowing for more leeway. Same is true for baiting the AoEs before going into the big line stacks, instead of mindlessly going into the AoE area potentially killing others. Or just properly equipping lost actions and using proper essences. It's personal responsibility all the way down. Always has been.