OK, if the virus is available why don’t we have a typical vaccine made using it?
Because it is too hard to do.
At least three previous attempts to make a coronavirus vaccine using killed or inactivated virus samples failed. The failure was due to the infamous Antibody Dependent Enhancement (ADE) reaction.
Which killed all of the laboratory test animals in each of those projects.
That approach was considered a dead end. The clever plan shifted to creating synthetic protein fragments from part of the coronavirus and provoking an immune response to them. What a clever idea!
So, which protein fragment? How about that S1 protein? It is stable and does not provoke the ADE response. And how do we generated it? Lets use RNA injections and get the patient to generate it themselves. What a clever idea! Have our lobbyists get some government sponsors and project money right away!
Oops. Turns out the S1 protein is toxic all by itself and causes pathological blood clotting. Just ignore those D-Dimer tests. They are not proof of anything. And all those heart attacks and stroke in 20-somethings and 30-somethings? Merely coincidental, we assure you.
Oops, the S1 protein can invade all tissue including the brain. But that vaccine fog will clear up in a couple of months, and it only affects a tiny percentage of the test subjects - err patients. Not to worry.
Oops, turns out the COVID virus mutates daily and has new seasonal variants of the S1 protein which evade the original immune response.
Oops, the new vaccine does not protect against the new seasonal variants. You'll need a booster after 8 months. Oops, make that six months.
Well, actually, if you die from COVID and your last vaccination was more that three months ago, we are going to classify you as "un-vaccinated".
Oops.
Of course, both have issues, so choose fast to market, but problematic, or slow and likely less problematic.
Well, the failure of 40 years of efforts to produce a coronavirus vaccine for any endemic human coronavirus might have something to do with that...