Honestly, it seems like the current devs don't play the game the same way that a player would. This "fix" sounds like it was theory crafted without actually playing the game and understanding how the existing mechanic worked in real open world gameplay.
The 30s vs 90s timer discussion makes no sense, because the way the Jade Protocol Buff worked before today's "fix" was that you only got buffed at the beginning of combat, and the buffs would not reapply until the next time you entered combat. The patch notes make it sound like the devs thought that it was applying repeatedly during combat. This was never the case and still is not the case.
Most classes and current builds in the game underperform in solo open world content because they lack the full set of boons that the devs obviously "balanced" the class around. The Jade Bot Protocol buff gave players a way to play for a brief moments with the full set of buffs (like with the training dummy) and only gave an advantage when grinding random trash mobs. The buffs did not last long enough to give a lasting advantage for Champion or Boss fights. As other players already pointed out, the buffs were lost in instanced content, WvW, and PVP.
I always felt like the Jade Protocol was the sort of thing that was intended to motivate Free to Play users to purchase expansions and upgrade their accounts without imbalancing open world play. It worked before, but it's broken now. It's just not worth the hassle of traveling to an EoD map (or Skywatch Archipelago) to apply the buffs, even for the extra Power, Armor, etc.
I've been playing GW2 for 11 years, and EoD felt like a backslide in quality for ANET, and now SotO is starting to feel even worse. I just don't feel enthusiastic about a future expansion with these kinds of changes to the game being rolled out.
The Jade Bot Protocol was a small thing that many of your PAYING customers enjoyed using for open world.
Please acknowledge the mistake and roll it back ANET.