As someone who has worked in London for many years, the difference is amazing. Biking in the city is now enjoyable, and the air quality is (subjectively, even without the data) dramatically better.
There was an incredible resistance to the recently introduced ULEZ (Ultra Low Emissions Zone) expansion, but I'm incredibly grateful for the sake of my children, if nothing else, that it has been pushed through.
I'm pretty sure I've shortened my life for having lived in zone 1 for so many years due to air pollution.
Cycling around London is also the fastest way for an astounding radius of travel. I can beat uber and the underground for most journeys using a Lime bike.
I remember about 20 years ago I was taking my bicycle on the train, and this involved a transfer through London. You can't take full-size bicycles on the London Underground, so I cycled across London from Kings Cross to Waterloo, and I definitely remember being reasonably terrified the whole way. If that has greatly improved since then, then that's wonderful.
That's a pretty short journey (probably about 15 minutes), but yes it will definitely be a lot better now. I think also part of it comes down to 1. getting used to it, and 2. the time you cycle at. Rush hour, while more hectic, actually is quite a bit easier because you're often going far quicker than any cars.
There was an incredible resistance to the recently introduced ULEZ (Ultra Low Emissions Zone) expansion, but I'm incredibly grateful for the sake of my children, if nothing else, that it has been pushed through.