It improved significantly. Level 1 to 30 was always a fun part of that game and it was balanced pretty well but once you got to the end game, it fell off a cliff.
They introduced Gear Sets and while the addition was a much needed one, it create a terrible meta. They could not balance the game correctly for the dark zone. At the start, only 2-3 gear sets were useful.
Also, it had a terrible loop for getting loot. Activities needed a certain gear score (based on difficulty level) but once completed, would only give out loot at the GS required to beat it. So basically, no matter how many times you beat the activity, your character would stay the same GS which stopped you from doing higher GS activities. The only way you could get better was to do the DZ (which had its own problems), or let higher GS players join your group and complete activities at a higher level you are currently. It was terrible. You would be stuck at a GS level for 20 hours before scrounging enough highend/gear set item which allowed you to repeat the same "Easier" activities at a higher level. Eventually, you would get a decent set which finally progressed you to a higher level.
But the worst was loot drops. They were minuscule. The only way to get high ends and Gear Sets was mission rewards and boss drops and when dropped, would be 1 item each. No other high ends and Gear Sets would drop anywhere else. But the ****ed up loop I mentioned above played into this....you could do a mission at your GS level but you would never get anything better. You had to go the DZ to get progress or re-do the Lexington mission a hundred times at the highest difficulty level and hope you got a decent drop. Just a reminder, there is a ton of different items you carry (6 clothing items and 3 weapons) so it was pure luck to get something good that you didn't already have. Around that time, only certain weapons were useful because of how unbalanced they were so good luck trying to get something decent. Hell, even if you received the right weapon/item, you still had to deal with RNG on what talents/attributes you had. I must of played the same damn mission 300 times or more before I got something good.
They fixed all that shit in update 1.4. Now, it's a really good grind and you can get loot anywhere.