Exactly, most situations when in poor traction scenarios, all cars are struggling to maintain their best grip. You want to minimize ANY slippage at all times, if you can.
That's false. Every snow type has different needs but all of them have one thing in common:
If there is not a small amount of slippage under acceleration, you are not accelerating as fast as possible. This is true on dry and wet pavement as well. I've found my Performance Model 3 to be amazing in straight-line grip under acceleration, even on uneven surfaces like packed snow with patches of pure ice. The key is to not put your foot too deep into the accelerator. You will squirt forward like no one's business. I've noticed this on slippery wet pavement too. All four wheels will be scrubbing hard to maximize forward thrust.
It's also true to an even larger degree when considering threshold braking, especially on loose surfaces (including snow). Early ABS systems on dual-sport motorcycles were widely hated for their long stopping distances on sand and gravel. They were not stopping quickly because they were overly aggressive in avoiding lockup. An expert rider could stop in much shorter distances. New ABS systems have largely solved this problem by allowing "micro-lockup". The wheel doesn't fully lock-up but it is turning much slower than the forward speed.