The point is that, at some point, the NHS has to be able to cope with Covid AND other treatment. If we don't get a vaccine we'll have to cope with Covid for months if not years.
Even if you currently think it's 'what amounts to a bad cold' @Thefrenchbaguette, there's a chance you or your family may need hospital treatment with this as the months or years go on. People end up in hospital with pneumonia brought on by chest infections or flu so the odds are any one of us on here will end up in hospital with the complications from Covid at some point.
So the government and the NHS have to find a way of treating Covid, the complications and carry on treating 'normal' illnesses and diseases.
Having said that I think you do need to bring up your DC issue with your MP and, as @HoneysuckIejasmine said, this seems to be a regional thing. My sister, having had a breast cancer scare a few years ago (which thankfully came to nothing), found another lump two weeks ago. She did a telephone consultation with our GP, got an immediate referral to the hospital. She went to the hospital last week for her appointment, had a scan and blood tests. She had a phone call this week to say the scan showed a benign cyst and bloods were normal. So urgent referrals are happening here. I don't know what's happening to routine appointments though.
Covid has thrown everything on its head but we need to get to a new normal asap because we could be living with this for many years, possibly in waves, and cancer/heart conditions/lung or kidney and all the other problems don't go away just because Covid is here. The NHS has to find a way through and we also have to learn a new way of getting these things done - whether it's different types of appointments to allow social distancing, wearing masks in hospitals or GP practices or different places dealing with routine things that hospitals used to deal with.