London buses may have wheelchair spaces allocated; they may have ramps to assist wheelchair users off and on. Sadly, what London buses do not have are very tolerant or understanding passengers.
You can put in place all the infrastructural access elements in the world. However, if certain elements within society then choose to ignore the infrastructural enhancements, then the thing becomes useless to those it was intended to benefit.
If other public transport users refuse to accommodate wheelchair users and other disabled travellers; if they refuse to move out of designated areas or even give us room to get on a vehicle, then access aids are pointless. On trains, if people block us in with luggage; or if they pile luggage in doorways, thus obstructing our freedom of movement; then, they are effectively pushing us off trains; they’re contributing to our sense of isolation.