It is a good deal but a little double edged.
The Basic Salary will be £67k in 2022 but to achieve the £72k you state you have to be at a London depot, includes their top rate London weighting (Regional Allowance) and a retention bonus.
I'd be interested to see what the impact of a retention rate is in the long term.
I very much doubt their London depot drivers will be moving to other London tocs now. I know they've lost a lot of drivers at Waterloo to overground and mtr crossrail.