While I'm not a wheelchair user, or regularly get on the bus with a wheelchair, I think in the past4-6 years ive seen 2 drivers stop someone from getting on the bus, one was the 47 (with the old Red Kite Deckers as the ramp was broke), and the other one was a Laser 35 as the ramp had broke (electric Mercedes) 

Any other time the drivers have been more than happy, even when some users say they dont need the ramp the drivers insist on putting it out