If Traction Control is already functioning when you are cornering, then switching it off will, if you are lucky, just make you slower as the inside wheel lifts. If you are unlucky then the loss of control will contribute to your high-speed accident. Have a grovelling apology ready for anyone you hit in the process.
TCS is sensing that the front wheels are losing traction, trying to rotate faster than the rear wheels, and reducing the engine output just enough to keep the power on the road. It is delivering the maximum power that your suspension and tyres are capable of putting down - at that degree of sideways acceleration in the corner. It was banned from Formula 1 cars because it made racing boring - everyone could get the maximum of power down all the time.
The TCS switch is there so that, on low-friction surfaces such as snow, mud or gravel, you can intentionally break traction with the rear wheels to
help you corner by opposite-locking.
With TCS off you still have EDL, which stops the inside wheel from overspeeding as it lifts off the tarmac by applying the brake to that wheel. This is intended to make moving off on poor surfaces easier (say one wheel on tarmac, one on gravel) If you are in this situation because you are cornering on the limit, the extra power will be fed to the outside wheel, making that lose traction, and you are no longer in control.