Depends on the surface. Once a wheel has started to slide on asphalt, the co-efficient of friction between the tyre and the road is reduced. As anyone who has done a burnout before will attest - breaking the traction and getting the wheel so spin/slide on the pavement is the hard part, keeping it spinning once traction has been broken is much easier.
Sure, snow/gravel where the is material piling up in front of the wheel may be different, but a non-locked wheel stops a car quicker than a locked wheel on good surfaces. That's not to say ABS is better than a competent driver threshold braking. But the vast majority of drivers in an emergency situation are NOT good drivers at that point in time.
Yeah but it doesn't work. All the R&D money just goes into research to make the engine last long enough at a higher power level now. Fuel restrictions, engine quantity limits, etc. just raise the R&D required and make the tolerances smaller.
The cost to stamp out X copies of an engine is the cheap bit. The expensive bit is the R&D to develop said engines. Engine and fuel limits in the name of cost saving is a total farce.
Senna's death was nothing to do with traction control, the last theory I read was that he ran off track due to suspension component failure. Plenty of things have been banned in F1 to slow the cars down - displacements and cylinder counts have been reduced, turbocharging has been banned, ground effects have been banned, active suspension has been banned, active aero has been banned, wing sizes have been reduced, grooved tyres were mandatory in the mid-90s to slow cornering speeds, etc.
"saving money". ha. Whatever regulations they instate, the teams with more R&D resources will do more R&D. All changing the rules does is give a new set of parameters to the engineers to work with.