Antonia
I don't think it's quite as simple as looking at inequalities, although I agree that this needs to be done. The virus attacks some people more severely than others, and the reasons are not completely understood yet. Some people in their forties have died, even with no underlying health issues, and some have long Covid. I don't think diabetes (especially type 1) and auto immune diseases are more prevalent in some ethnic groups. They happen in all groups of society.
It's true that poor living and working conditions favour the spread of the virus, and these ought to be a priority for the government to tackle. I doubt if they will be though.
'We're all in it together' means that it falls on all of us to do what we can to get the virus under control.
But many health conditions are related to inequalities and there is also an enormous body of research that shows access to and use of health services is related to socio economic status for a whole variety of reasons. On simple example is time off work for a medical appointment or treatment. It doesn’t matter what your ‘rights’ are if you’re in a precarious poorly paid job. All in it together is I think a very anodyne meaningless cliche when set against the reality of exactly what ‘it’ is we are all in together.