Why does OptiFine bring my Minecraft to a standstill?

But it hardens my Minecraft.

Is that due to the hardware or OptiFine?

've already set all OptiFine settings to "Off".

Optifine is a graphic modification and accordingly draws performance

But I've set everything to "Off" and OptiFine should (partly) prevent laggs right?

What components does your PC have?

Intel Core i5 and no graphics card (is a laptop) but play mods and on large servers etc. Always worked lag-free

This is probably because Intel HD graphics is not intended for gaming but for working, optifine consumes power even when everything is off

That is probably due to the graphics chip. Try without mods and only Optifine.

I know that, I and my friend did a test (for YT), or did we want: LiquidBounce vs Hera, He with LiquidBounce and me with Hera, Hera installed OptiFine. Then we tried Xero vs LiquidBounce and it worked, although Xero also has OptiFine