The reason people are upset is because many players who play Skyblock extremely actively are quitting the server, while I agree getting rid of bedrock players is bad, I can see where Rex is coming from in the sense that, 4 months of work was wiped out with one update for a lot of players, therefore they don't want to play on Skyblock anymore.
The reason I say 4 months of work was wiped out, is because with this update, you cannot simply "take a few chests off" to fix the hopper issue, as it bugs out and tells you that each line of chests has a different amount of hoppers, breaking an entire chest line. Some people have an extraordinary amount of chests, therefore fixing them would take days, or weeks. You need to remove the ENTIRE line to sort the hopper limit. I even have a section of my island completely bugged, where it says there are hoppers that don't exist.
Us as players, over the last four months have had to edit our islands multiple times to account for the changes, I can see why people are tired of having to edit what they've done what feels like far too often nowadays. Although reading that there will be minion changes to accommodate for this, I feel like it should've been accounted for before the server was reset in December, realizing that there would be an enormous amount of hoppers used as Slimefun was removed. People are so quick to say the "NoMoreSlimeFunForMoreFun" but they do not realize how much Slimefun was used in regards to storage systems, the Quantum Storage was extremely invaluable, and while it was also quite buggy, with networks turning into regular glass, and it being a buggy, outdated plugin, if people had actually paid attention to Skyblock before, they'd have realized every player who played Skyblock before the reset used Slimefun storages, as you could store millions, and billions of items inside one block.
Ultimately, the changes are felt by the Skyblock community. There are people who play every day, who contribute towards the Skyblock community heavily, as well as the server, who simply do not want to play anymore because of the changes to hoppers, and I don't believe it is specifically because of hoppers, I believe it's because the changes to Skyblock are so frequent now, with people extremely often commenting that they are worried about building as it may be for nothing if there is a "nerf" we have lost a lot of very active members as a result of this.
As Starlethe had stated on the server after this hopper reduction happened, we, as a community are smaller sure, but that does not mean we are not worth anything, and it would have been nice to have a poll, or even a conversation on the forums, with the opportunity to come up with solutions, or even be alerted to the changes prior, without waking up one day and wondering why months of work is irrelevant.