A piece of software being closed-source means that the source code is not publicly available anywhere. Usually, the software code is obfuscated as well, meaning that even if we have the piece of software, we still cannot view its code without dedicating more time to decompiling it.

Closed-source software exists everywhere, so you might be wondering - "well, why is that a bad thing if there is a lot of closed-source software that we use?" And while that may be true, Minecraft modding is very different.

Minecraft modding can be very limitless, but this is because of one thing: Minecraft mods have access to (almost) your entire computer. This makes it very risky to run mods, which means that we have to trust the code that we are executing.

But, the very nature of closed-source and obfuscation hinders that in a very big way. If we cannot see the code that is being ran, how can we trust it won't be looking through our files? This is why mods being open-source, as well as being unobfuscated, is a big deal.

Note: This isn't meant to imply that Essential is accessing our files. In fact, making it closed-source makes it less accessible for anyone (besides Essential devs) to verify if that statement is true or not. Also, Essential itself is not obfuscated, only closed-source.

2nd note: Essential itself is closed-source. Its libraries that other mods can use (so Vigilance, Elementa, and others) are open-source and available on GitHub.

In a game primarily played by children, Essential decides to push their microtransactions system, where you can buy Essential Coins and exchange them for cosmetics in-game.

While this doesn't seem necessarily bad at first, and it is true that this is one of the more reasonable monetisation methods out there, the issue stems from the method to obtain coins.

The reason why this is an issue is due to the coins only being bought in bundles, meaning people will most likely have to overpay to get a cosmetic, and then leave a bunch of coins they paid for just sitting around, doing nothing.

It is understandable that Essential has a monetisation method, as it is a company with employees. However, coins only being obtained in bundles shouldn't be the case.

As a mod for Minecraft, it really shouldn't be trying to break other mods, and as its name suggests, really shouldn't be doing much with Minecraft itself aside from letting your friends join your singleplayer worlds. Yet, this is untrue.

For some reason, Essential's code interacts really weirdly, mostly when playing with other mods but also sometimes with Minecraft itself somehow. This has led to countless incompatibilities in one way or another, with many mods.

Essential's closed-source nature means that it takes time to be able to troubleshoot fixes with Essential without having to brute-force a solution, time that is either not available or could be better spent improving mods.

It is important to note that according to Essential they will make their mod source-available at some point, making it easier to fix incompatibilities. However this has been months on end now and it's unclear if they still plan to.

For a mod described as the "essential tools for Minecraft", it packs in a bunch of not very necessary things that just make the mod feel more like bloat and less like being a necessary toolkit to enjoy Minecraft at its fullest.

Sure, it's very useful to have a world host function, a friends list function, a chat peek function and a zoom function. These are all well and good and in fact these have been so nice to have they've been recreated into separate mods.

However, we can't say the same for the cosmetics, emotes, and the account switcher (which yes doesn't fit for most people). Mostly the cosmetics, since you can disable cosmetics only for yourself and players wearing armor (which isn't always the case).

The cosmetics can also hamper the FPS a little bit due to the required animations and this would only get worse if multiple players in the same world/lobby are wearing cosmetics that have unique animations.

With the many features Essential has, there has to be an area to put buttons to these. And, if you look at the main title screen, you can see that Essential has... a lot of buttons there. This leads to a cluttered UI.

The result is that it becomes too intrusive, almost like Essential is the main focus, not Minecraft. Especially on a new instance, the amount of screen space taken up by Essential alone makes it cumbersome to navigate (Not helped by Minecraft's auto-GUI scale).

Also, some of the buttons there are not necessary. For example, the Host World button is a button that no one ever really clicks, so having the button there hurts more than it helps. Similarly, the Minecraft Folder button is not a button that most people will use, and having it takes up more of the screen which with how it looks already, is not particularly a good thing.

It is important to note that the split between the necessary and unnecessary buttons on screen can be arguable. For example, the Hide Notifications button can be useful if you want to have a peaceful session without being hit with notifications.