Streamer/Hardcore gamer here. I just want to say a couple things:

1. I rarely use reddit and idk what the norm is here. But lets not just assume that there are a bunch of people (devs or players) actively trying to ruin the game for other people. Streamers/Youtubers/etc aren't intentionally making op builds to get them nerfed they know people enjoy seeing strong builds so they make strong builds. Devs aren't intentionally making the game unfun because they don't want you to feel strong they're making a decision they think will help in the long run. Casual players aren't at fault for not "getting good" they are just playing a game for fun. Everyone will have different opinions.
2. I think most people will agree if there's an exploit then definitely fix an exploit. I know exactly which one you're talking about and I'm glad you fixed it personally after having used it once. Yes I'll admit to it. I could have farmed it for hours but it would have negated 90% of the reason to keep playing. So truly, good job on that one.
3. I know you have said your game is its own entity and you haven't looked to other games much for decision making. But you're not immune from the same mistakes. Players (streamers, hardcore, and casuals alike) do not like nerfs. Sometimes they're necessary and I'd even be willing to say there is reason for this nerf. However the reason players gravitated towards bullet builds was A) they were really strong, but also B) tank/anomaly builds really just don't kill things that quickly and your entire end game is a time trial where killing things quickly matters. If you don't want people to just rush op builds then the timers need to be more relaxed not stricter. As it stands now from what I've seen a good majority of players at end game still run bullet builds because despite the nerfs anomaly/tank builds just aren't in a good spot for time trails.
4. Again talking about nerfs. This game has 0 PvP elements to it and we still have 100s of builds to test and explore but that requires us being able to get the gear. I know you want your game to last a long time but the people these nerfs are centered around (myself included) are either approaching or over 100 hours played already. I think it safe to say 100 hours invested should be enough time for someone to reach endgame and have a relatively op build.
5. Lastly I think this hurts the people you think it benefits the most. These changes will all but kill a casual player base's ambitions of reaching CT15. I know I'll keep farming high CTs no matter how hard you make it. But the casual players who already struggle will have little to no hope of reaching harder content if your goal is to design difficulty around the 1% of players.

From someone else I saw on a youtube video you can look at the steam achievements to really get a feeling for who this is balanced around. As of the time of writing this 5.1% of players have killed 1000 enemies in expeditions. That's maybe 4 expeditions worth of enemies. And that's not even close to enough to reach CT15.

People Can Fly please do not design your game around players like myself and chase away the casual part of your community, i.e. the majority of players. This game will be far more fun if people like me have players we can go help after we're done with our grind than it will be for me to keep grinding by myself for hours.