18w43c Chunk Generation Suffering Extreme Lag Issues

When loading into or creating a world on the 18w43c snapshot, it doesn't take very long to get past the initial world setup, but chunk generation is nearly broken and takes more than 5 minutes in some cases, resulting in initially spawning into a world with just the void and sky.

Normally, I don't have any issues playing Minecraft on this computer, so this issue is affecting the playability of the game at this stage.

NOTE: This is even with every setting in the game set to the lowest it can possibly go.