Not the guy you responded to, but…
My group doesn’t do M+ basically ever. Pushing even 10’s is rare, and usually when we get together we do ~5-7’s. A few of us play together regularly, but almost never all 5 of us.
We were playing alts in the 400-410 range, with an odd-ball group of Guardian/Disc, Frost Mage, Sin Rogue, and Balance druid. Pretty much all of us were out of our comfort zone. Enchants, gems, consumables? We flasked off the start, that’s about it - most of these chars were fresh 120s right around the start of 8.2.
None of us had any prior knowledge of the dungeon (other than avoiding the boss the Aerial Oppression Unit was above). We did not look up guides, did not ever even look at the dungeon journal.
2.5 hours later, including a long disconnect, several pet battles, and sight-seeing for screenshots, we cleared it. Most bosses were killed on the second or third attempt. First attempt was always “we have no idea what is about to happen!”, and despite that we almost one-shot King Mechagon and in fact we might have even one-shot the boss before him. Grunker was the only boss that felt overtuned. K.U.-J.0. feels… off, and slightly bugged, but very easy once we found out how to work-around the weird LoS issue.
A few trash packs felt disproportionately more difficult than the rest of the dungeon. Most of that was also mitigated by 1-2 CCs.
This is only the first week of the dungeon which is intended to be a step up from regular M0 in both difficulty and time-investment. If you pug it with people who might not even know what their interrupt does, fail to learn or teach the fight to others, and get upset after you’ve died more than 0 times, yeah - you’re not going to have a good time. This dungeon, as it currently stands, is not for you then.
Improve yourself, research the fights, come back with friends who listen to instructions, wait until the community as a whole is more familiar with the dungeon, or wait until it inevitably is released as a 2-part Heroic dungeon. It’s even conveniently split into two distinct sections with 4 bosses each already. It’s coming.
A few very specific parts need very minor tweaks. That’s all.