It was a given that SARS and MERS vaccine projects were going to get dropped pretty quick given how small, short, and not really spreading outside the outbreak zone those were.
This stuff costs hundreds of millions to develop and test - so carrying on just off the chance that it may end up useful 10 years later for a related virus is never going to happen.
That's not even then taking into account the costs for production, distribution, etc. Not to mention that likewise, people likely won't queue up to get vaccinated for a virus that was a blip on the radar just in case a similar one that spreads more might show up later.