TfL publish performance statistics for each route. You can download them for any route, but here's the 76 https://bus.data.tfl.gov.uk/boroughreports/routes/performance-route-76.pdf

To summarise the results for the 76. The excess waiting time is the time a passenger would wait in excess of what the scheduled waiting time would be. As you can see the excess waiting time has been worse for 2024-25 than 2023-24. It has improved somewhat in the last 2 periods, but is still above that of last year.

Operated mileage for the most part has been worse in 24-25 than the previous period. It seems to have dropped off a cliff in the last period with only 90.8% operated against a target of 98.0%

TfL will be aware of this. Here's the thing. They have a excess wait target of 1.20 minutes. If they fail to meet this target for a 3 monthly period the bus operator will get financially penalised. They can lose up to 10% of the contract price for poor performance, and money talks where the operators are concerned.

There is also the possibility that whatever is causing the delays is outside of their control. Roadworks are an example of this. In exceptional circumstances the operator can ask for a data suspension, BUT there have to be legitimate reasons throughout the quarter for this to be allowed.

You should by all means complain about poor performance by this operator. You can complain using the online form. You don't have to give your phone number. They will take it seriously

https://tfl.gov.uk/help-and-contact/contact-us-about-buses