Why does Minecraft beta feel so right?

I play modern Minecraft mostly

Due to create mod being present there.

I played with beta texturepacks and nostalgic tweaks for lighting sounds etc, but it never managed to replicate the beta feel.

For some reason, beta versions are beautiful to me, while in modern Minecraft it's hard for me to play without shaders.

It runs so smoothly and there's something in the gameplay that makes it more comforting

Why is that?