To be fair, it is a much bigger incentive than usual (easily the biggest incentive since smallpox). And the technology has advanced much more than before, several vaccines (which are completely different from each other) were built within 6 weeks or so of the genome sequence being sent from the Chinese researchers.And as many have said before a vaccine typically takes 5-10 years to get to market. 12-18 months would be unprecedented (drink). The only way to speed things up (assuming all goes well at each stage) is to miss out some of the normal testing and go almost straight to trials on health volunteers. Which is hugely risky and illegal in most places.
I think it is quite understandable to go faster than usual. For example, it made sense to do parallel trials in both humans and animals. Of course, I believe that the researchers who are doing this are extremely cautious.