It really seems like there needs to be some major changes to buff, enemy damage, and enemy armor...and some people won't like even though it won't hurt them one bit.

The issue it seems to me is that because a lot of player buffs and damage stack to stupid levels the amount of damage that enemies have has grown to stupid levels as well.

The assumption that a group of four players will be buffed to ridiculous levels means that enemies have been given a huge damage pool that any normal play could never surmount.

I think this from the video below has broken it down rather nicely, he identifies the biggest issues as: Sentry's Call, Tactical Pulse and Smart Cover. The ways those work and stack in typically high end builds make "The Division's" end-game impossiblke for casula gamers, thus making it effectively impossible for it to be effectively tune.

I have found that the only way to really complete our understanding how to play the game after lvl 30 Single player stuff or after level 20 Dark Zone is to watch some video.

I pretty much figured out that I was being too "offensively minded" in my build, I was putting too much effort into my hitting power with weapons and not enough into 'damage mitigation' buffs. I thought I was doing okay with armor, but just a pure armor score in not enough. Or, rather a players armor score is one tiny component of any players "over all protection from damage".

The other nice thing about watching high end players is you see some of the best players get wasted and often need to be revived. I tend to be what might be equivalent to a "Burst Damage Deal", I deal a lot of damage fast, but unlike a tank I can't keep getting hit. I have to take a lot of cover and pop up to deal damage while a take in distracting an enemy. With that said, I was behind the curve on mitigating damage coming my way; I needed to put more perks into damage mitigation. That meant dumping Turrets in favor of Smart Cover. I already do enough damage with my gun very quickly, so the turrets were redundant where as I needed the buff Smart Covered offered. Because, I don't trust everyone to toss health when needed, I still kept my the skill for tossing Support Stations.

If you are fining you are just not being successful in The Division I would watch some videos by Skill Up. He does tutorial videos for The Division, Dark Souls, Overwatch and Destiny; but most of his focus now is on The Division. He had the advantage of not being a jerk and explaining things very well and thoroughly.