At present it isn't - You have to be out of the car so as not to be deemed to be in control of the vehicle.

That's not the case. As long as you're parked, engine off etc, then calls are legal.

As GB says the change is to deal with the increase in phone functions beyond 'interactive communication specified in the last round of legislation. Main objective is to deal with filming while driving and use of game apps.

Still only applies if you're actually holding the handset. If it's in a cradle or elsewhere but integrated using Bluetooth or similar you're fine. I've recently discovered, having Bluetooth on all the time for the Covid App, that my phone integrates with the Fabia and that I can make/receive calls from it's touchscreen, sound through the speakers and presumably there's a mike somewhere.

Very much doubt anything will happen, we do not have the Police to stop the amount of drivers using mobile phones in the hand, everywhere you look someone is holding one and in a lot of cases Texting, or using a map in the hand.

What it will do is remove the need for the prosecution to prove that the phone was being used for "interactive communication." This case in April 2019 reinforced what was written in the legislation (which makes it surprising that nobody had challenged it previously):

www.judiciary.uk/wp-content/uploads/2019/07/19-07-...f

At present it isn't - You have to be out of the car so as not to be deemed to be in control of the vehicle.

Do you? You have to be "driving" to be guilty of the offence. You can be inside a vehicle but not driving.