"If you want the government to give the energy companies massive cheques then why not say so?"
Because that's not what I want. It should be painfully obvious to anyone that if a private company can't make a profit while charging what people can afford, then they've failed. And if what they're selling is an essential service, then that service should not be in private hands. The cap and associated bailouts aren't an argument for government subsidy of private industry; they're an argument for nationalisation, which is also what is happening to EDF in France. And before anyone goes off about "lefty nonsense": the TUC has costed out privatisation of the Big Six at less than the cost of the bailout issued to cover Bulb.
Re: profits - I'm not talking about a single quarter for BP. It's all of them. BP did indeed suffer large losses in 2020, but their 2021 profits were an 8-year record and have only continued to increase in the first six months of 2022. Centrica made £262m profit in the first half of 2021; in the first half of 2022 they made £1.34bn. And Shell's profits are also surging to record levels, with Total's not far behind.
Sources:
https://www.itv.com/news/2022-07-28/british-gas-owner-centrica-profits-rise-to-134-billion-as-energy-bills-surge
https://www.reuters.com/business/energy/bp-records-highest-profit-eight-years-2021-2022-02-08/
https://www.ft.com/content/39cc3cb6-b054-438b-819d-e391c0701e44