Printing time is all over the place, never accurate

Basic Information:

Printer Model: LDO Trident 300mm
MCU / Printerboard: Octopus
Slicer: PS latest

This problem is driving me mad, I never know how long my print is actually gonna take to finish.
I printed this guy yesterday: azure-cloud-wyrm-kijaidesign-02_0.2mm_PLA_11h7m_88g.gcode

As it says, it should have taken 11h but it only took 9h to print.
All my prints are this messed up.

My old MK3S+, 11h is 11h
My returned BambuLab X1C, 11h is 11h
This Voron, 11h is god knows

That also means that checking Mainsail is useless since the whole timing thing is broken.

Why can’t this printer deal with time just like any other printer???

I have been using klipper_estimator, it helped a bit but clearly didn’t solve the problem.

Looking forward for some solution, this is madness.

Thank you