Mostly incorrect, entering the BIOS and having the toggle to switch between S0 and S3 (or, "Linux") sleep does indeed exist but it is hard to identify what models have it (I hear Lenovo's BIOS simulator helps) and it's increasingly being removed in newer models or even removed in updates. Dell has no interest in putting it back and recommends hibernate or just powering off the machine when on-the-go.
I made sure the ThinkPad I own personally had the toggle but my work-issued one does not so it is now a Hibernate-only machine. No setting can help that.
If the BIOS says it supports Modern Standby, Windows takes it at its word and completely disables the ability to enter S3 sleep (classic standby). There’s no official or documented option for disabling Modern Standby through Windows, which is incredibly annoying.
Side note: for a while, there was actually a registry setting you could change to disable Modern Standby on the Windows side. Unfortunately, Microsoft removed it, and to my knowledge, has never added it back.
I'm not a Windows user, so I can't confirm one way or the other, but toward the end of the end of the article the author gives vendor-specific instructions for disabling the S0 Low Power Idle capability from BIOS.