The simple and straightforward fix is to kill all the mobs who are occupying the space. This article informs players about different ways to kill all mobs in Minecraft.

Minecraft mobs drop all sorts of loot, some of which are pretty valuable. A lot of them drop food or other useful crafting, so it's a good idea to farm them.

Here is how you can kill all mobs in Minecraft with a simple command. This guide is for both Java and Bedrock editions of Minecraft.

Need XP fast in survival? This tutorial shows you how to build the easiest mob XP farm in Minecraft 1.21+ — no spawner ...

Minecraft Legends lets players control and direct new and returning mobs using strategy game mechanics that can sometimes be a little complex.

To control mobs in Minecraft Legends, players can either have them rally, send them to charge forwards, or focus on specific targets.

Control your mobs in Minecraft Legends Every command has a name, specific control, and end result that the mobs will perform if they are close enough to you.

Minecraft Bedrock Edition players can edit their world settings under “Game” and uncheck the box next to “Mob Spawning.” Java Edition players can type “/gamerule doMobSpawning false ...

Now modders have taken the mobs shown in the Minecraft Earth videos and added them into the Java edition, using a bit of artistic license to create mechanics for them.

Though not verbalised it certainly looks like that means you will be making an army of mobs to fight against The Nether. Classic Minecraft stuff with a whole new look.