Also George Osborne cut TfL's public subsidy so that for the last five years it's had to raise its own revenues itself. Unsurprisingly Crossrail barely got over the line (even without getting into the delays) as a result, and all of the other future works that have been carefully planned out and consulted on and budgeted for the next 20 years are now on indefinite hold - including Crossrail 2, which Johnson seems to think can be conjured out of thin air.
And of course the Tories have been repeatedly hammering "Sadiq Khan/Labour have bankrupted TfL" in each election here, and of course it doesn't work because it's such a flagrant lie. We're still saddled with Johnson's shitty buses and cable car - his legacy here is spending loads on pointless whims, he has no standing to accuse any other mayor, Khan or anyone else to come, of being poor with money.