[Myrddin]

Some of the seasonal flu viruses are Coronavirus...just like COVID-19. Coronaviruses continually mutate. Trying to make a vaccine to a continuously mutating virus is a fool's errand.

[DEPcom]

“Some of the seasonal flu viruses are Coronavirus”

Both are contagious respiratory illnesses. They are caused by different viruses. Covid-19 is caused by Coronavirus and the flu is caused by influenza viruses.

Seasonal flu viruses are caused by viruses.
Colds are caused by Coronavirus.

Both do mutate. The cold mutates more then the flu, that is why we do not see a vaccine for the common cold. I bet we do not see a good vaccine for Covid-19.

[2aProtectsTheRest]

"Some of the seasonal flu viruses are Coronavirus"

No, they are not. They aren't even the same phylum. Influenza and coronaviruses are as closely related as human beings and snails.

You might be thinking about cold viruses. Some cold viruses (specifically four known cold viruses) are coronaviruses. Most are rhinoviruses. In total, over 200 different viruses cause the symptoms we collectively refer to as the "common cold". But the flu is a very specific family of viruses which are not even remotely related to coronaviruses or SARS-CoV-2, which is the virus that causes COVID-19.