Tcs doesn't only cut power, it can apply braking force as well. Remember that to gain traction you want the wheel that's lost traction to slow down, thereby getting it back. Especially since it's tied in with ABS now, going around a corner and the back wheel hits water loses traction, bam tcs kicks in for a second to help it regain, preventing a possibly accident.
Saying people should drive better, makes it feel like we should just get rid of airbags and abs while we're at it. My first 3 cars never had such fancy malarkey.