I can see a point in the future that tax on non ev vehicles will be prohibitive and then how will you have freedlm of choice.
It has always been the case that choice is a luxury reserved for the rich. As we become poorer, our choices become fewer.
Government policy reflects the wishes of society, and the 'polluter pays' principle reflects the prevailing mood that in general, people should not continue to pollute our environment - hence the tax restricting your choice. Seems fair enough to me.