London has a congestion charge, which is a con, nothing to do with congestion, it's a straightforward tax, which is why most embassies in London do not pay it. London now has spy cameras looking at number plates to see if you're a "polluter", real reason is just to collect lovely data on drivers for the police and spies etc.
The new London mayor Sadiq Khan is short of money because he made an election promise to freeze public transport fares, that's impossible to keep without slashing services. Then there's the UKP38m (so far) stolen from taxpayer's for a pedestrian bridge nobody wants, and has no use whatsoever apart from to the corporations that want it as their taxpayer funded plaything.
So, instead of thinking about this as getting back at VW for their emissions cheating, it's just a tax rise to plug black holes in the mayors fraudulent spending.