You're treating the event as a binary--but it isn't. Zoonotic jumps happen when you have an animal virus capable of infecting humans and you have contact between humans and said animal. The thing is such contacts aren't a one-off, if the potential exists sooner or later it's pretty much bound to happen.
What we should be doing is studying the viruses that appear to have the potential to be pandemics. We got lucky in this regard with Covid--we didn't actually engineer a vaccine in a year. Rather, we had been working on a SARS vaccine for many years, it had been taken as far as it could be without human trials (and since there were no cases of SARS around human trails were impossible.) The mRNA Covid vaccines are simply the old SARS vaccine with some tiny edits to the payload--what took the year was the human trials, not the creation of the vaccine. That took IIRC 2 days.
What we should be doing is studying the viruses that appear to have the potential to be pandemics. We got lucky in this regard with Covid--we didn't actually engineer a vaccine in a year. Rather, we had been working on a SARS vaccine for many years, it had been taken as far as it could be without human trials (and since there were no cases of SARS around human trails were impossible.) The mRNA Covid vaccines are simply the old SARS vaccine with some tiny edits to the payload--what took the year was the human trials, not the creation of the vaccine. That took IIRC 2 days.