Copy paste from another airliners related forum; IMHO quite reasonable posts:
Nr1:
The best thing about a vaccine, quite frankly, is that it will calm people down and go a long way towards reducing the utter hysteria surrounding this pandemic which is what is causing all that economic harm.
It will not stop the virus dead in its tracks, will not eliminate it and will not prevent thousands from dying from it. All it needs to do is to bring the harm to below the level where people have an irrational fear of it, whatever that may be...
And, yes, I agree. The mechanisms that dictate medical research are great at ensuring the safety of the final products, but very much not adapted to quickly react to a fast-paced and lare scale event like this one.
Nr2
Agreed, even a universally available vaccine will not eliminate this virus. Too many people will refuse to be vaccinated, allowing pools of infection to exist indefinitely. I think that smallpox (la petite variole), for example, would still be around if there had been a large number of anti-vaxxers 50 years ago.
I also agree that exaggerated fear of the disease must be causing economic damage. For example, here in England there are many people who will not send their children to school, making it difficult for some people to return to work.
Fear is also shortening the lives of some people who are too frightened to visit doctors when they have symptoms of diseases (eg some cancers) where delay in treating the disease will result in them not surviving the disease - an outcome they could have avoided.
Nr3:
There are huge political and economic pressures to have a vaccine ASAP to the public Russia would love to beat the USA and Europe with a vaccine first, to help with internal politics, make Russia look great and Putin look like a great leader. China's leaders have pressure on them as where Covid-19 originated, to be able to use an early vaccine for domestic politics, make China look great and as a way to extract trade and other concessions or use it to gain access to mineral wealth, consumer product sales in 3rd World countries (as already doing unlike the USA) In the USA, Pres. Trump is running for re-election and is desperate for something he can make a lying claim to have caused a vaccine to be available to win, to cover for his massive failures to deal with Covid-19, deal with the desperate need for people to be able to go back to paying work, schools and have a life again
There are several big areas of problems I see with vaccine(s) in the USA.
One is will it be effective and without bad side effects. Attempts to speed up a vaccine to the public puts up a huge risk that could make things worse. You tame the disease but end up with worse diseases and illness.
Second will be that many, perhaps 30%, won't take it as don't trust our government, our drug companies or scientists
Third will be the likely mess of the distribution of the vaccine. While it is clear that health care workers, first responders will be in a first wave, we know many will cheat, steal, lie, pay off politicians to jump the line to get it. Then will be the battle of who's next persons with co-morbilities, over 60-65, 'essential workers' like in food preparation, farming, ranching, teachers over retail workers and so on. Many parents of school kids will want them vaccinated first before them out of love and to get them back to school safely. The distribution of the vaccines being developed will require expensive and more that current capacity of special freezers and storage facilities, expensive and difficult logistics. Then there be claims of racism and classism, if a blue/Red state, city or rural area, all saying they are being ignored while others get it first. This could be further compounded by the need for 2 or more shots. There could be improperly made and rejected batches, screws ups in distribution, shortages of syringes and PPE that will slow distribution so it might take well into 2021 before enough get the shot
Fourth will with a vaccine out and distributed, many prematurely ditch preventive measure like masks and social distancing, opening up businesses, allow nonrestrictive travel, social activities as if the virus never happened.
Fifth will be the need to assure supplies and distribution of the vaccine to 7 Billion people, most of which live in poor countries. Many rich countries will take care of themselves first and unlikely to financially support vaccination outreach as cheap, greedy and selfish. If the rest of the world doesn't get the vaccine, international travel becomes impossible and no one should accept many millions dead.