Let me preface this by saying that I love Path of Exile and have played it fanatically since back when the game only had one act. I loved the genre since I played a demo of the first Diablo game as a 10 year old. Path of Exile revolutionized a lot of the staple ARPG systems and mechanics when it came out, since there had already been a couple iterations of the genre after Diablo 2 (Torchlight, Titan Quest are the main ones that spring to mind). Path of Exiles passive skill tree, itemized gem skill system and amazing customization and depth were a fresh breath into the genre.
To be clear, the early history of the game wasn't perfect. A lot of the greatness of Path of Exile comes from how they manage to extend and iterate upon their core formula to make the game better and better. It hasn't been a straight, clear path for them, but for over 10 years now they've continually pushed out expansions and updates to their game.
The Current Trajectory of the Game
The way GGG lined things up for Path of Exile 2 (which is purely a marketing gimmick, its the same game, so lets just call it as it was originally called, 4.0) GGG plans to incrementally introduce balance changes (both for loot and overall power creep), engine changes and various other minor additions to the game before the full release of 4.0, with the new Ascendancies, new campaign, new gem skill system etc. Crucially, power creep has been rampant for a long time, particularly with leagues like Harvest and Delirium (even with the heavy subsequent nerfs they had post-league).
So we all knew a nerf was coming, but the one we actually got in 3.15 set the game on a trajectory that I feel is the worst the game has ever been.
I will say that actually attempting to balance the build meta of a game like Path of Exile is a difficult prospect, so I don't judge GGG too harshly on this. Even though the number of actually viable, end-game performant builds are nowhere near what a newcomer might think is the case when they look at the passive skill tree, and then see the 270+ active skill gems to choose from (with support gems on top of that), its enough to make things very difficult. As an aside for a newer player reading this, in actuality many builds will share similar trees, and over time GGG has even actively sought to streamline and funnel players into certain thematic playstyles, mostly associated with a specific Ascendancy class. I personally consider this another failing of the game in its current state, but there's enough to say about it that it would deserve its own post, so lets leave it at that.
In 3.15, the method of bringing in the power creep ended up being a blanket nerf to most every support gem, to cut down the damage multipliers. A fair solution that hits everyone equally, you might say. Unfortunately, every build isn't equal. Pre-3.15 there were a plethora of borderline viable builds, builds that after the nerf were suddenly not-viable. Meanwhile the most overpowered builds kept chugging along, because what is really the difference between 50 million DPS or 40 million DPS?
If it stopped there, we might just have been able to simply move on, but it didn't stop. For some reason they felt that mana costs should be touched on, to the point where one of the weakest build archetypes, self-cast builds, became extremely difficult to play (funnily enough, this is an archetype they paid particular attention to buff in 3.17, but still neglected to address the mana situation for them). On top of that they also made this change apply to most trigger builds (CoC, CwC, etc) and as a result made those much, much harder to build for. With the further 3.17 nerfs to trigger builds, they pretty much started nailing the coffin of these builds.
This kind of sums up the state of the game to me and the current trajectory of balance GGG is set on. Instead of nerfing the worst offenders, and taking a more careful approach to blanket nerfs, they enacted this clumsy strategy which ended up even further homogenizing viable builds, which I guess lines up with their design philosophy of recent years. Most every league I played in this game, the main staying power of the game was exploring the fresh build meta each patch, usually I would easily have 5-10 builds that I wanted to do over the course of the league. I find that number dropped to almost nothing this league and my will to play pretty much zero as well, despite the new Atlas tree possibly being one of the best additions to the endgame in years.
Hopefully 3.18 will herald an end to these clumsy nerfs, but at this point I worry that Path of Exile has simply stagnated. Even with 4.0, I don't hold out too much hope, but hopefully I'm wrong.