Liero IS awesome: https://www.webliero.com/

And Hedgewars

I wish I could remember one of these games in which players were tiny cars with ridiculously ominous names like Monsieur Murder (i'm paraphrasing but that was the vibe)

Micro Machines? Slicks n slide?

Re-Volt?

Only for Playstation consoles, but might have been one of the Twisted Metal games.

RC Cars

Was one of the cars called inferno? Did you have to press alt to hit nitrous?

I played a localized version so I don't know the names in English sadly, but the alt sounds right

The graphics were super simple, flat colors

I too had a childhood game about tiny cars that I couldn’t remember.

My game turned out to be stunt gp.

That looks more like it! But not quite there yet. Thanks for sharing

Ah good old Soldat. Modded this into oblivion using notepad and mspaint.