Actually it's not so bad - the central line at rush hour is abnormal.
Not sure how productive it is taxing buses...
The new taxi regulations are a welcome improvement [1], but they're weaker than they should be. Why are Euro IV cars still allowed as new taxis? Why is it only voluntary for >10 year old vehicles to be replaced? No doubt it was the best deal Kahn etc could get, but it's disappointing that London/Britain can't do better.
The buses[2] at least, are all Euro 4 standard or better, with the majority Euro 5 or better, i.e. made since 2010.
[1] https://tfl.gov.uk/modes/driving/ultra-low-emission-zone/tax...
[2] https://tfl.gov.uk/corporate/publications-and-reports/bus-fl...
The buses still have to go somewhere though - the huge number of routes along Oxford Street is not about serving Oxford Street per se so much as about getting them across town. Honestly I'd be surprised if buses were the big source of pollution though - the fleet is quite modern and many of them are hybrids that deliberately run electric-only through the most polluted areas.
Why?
1) Traffic is terrible. It will take 1hr+ to do a journey the central line does in 15-20m.
2) Even if you want to drive, parking costs around $1500/month in the square mile.
3) On top of that, you have the congestion charge for entering central London (£11.50/day - soon to be £25/day if you have a particularly polluting vehicle).
You're looking at about $2000/month if you want to drive, which takes 4x as long and costs about 15x more than the train.
This is what happens when you price effectively for the externalities of traffic congestion. People will switch to transit en masse, and 'loud music' will not be seen as a problem.
[1]this also means there is the political will to build massive transit infrastructure, like crossrail, which will relieve the central line at a cost of around $20bn.