No, it's not "a nasty virulent cold virus" - that's like saying, "all dogs are mammals, therefore all mammals are dogs."
It's a virus from a very broad family of viruses that are grouped together because they appear similar to the human eye when looked at under a microscope. It doesn't mean the four coronaviruses that cause colds (229E, NL63, OC43, and HKU1) are that similar to SARS-CoV-2 in terms of how they work and therefore how you would go about creating a vaccine. For instance, the receptor of the most prevalent cold-causing coronaviruses is aminopeptidase N, while the receptor of SARS-CoV is ACE2 - so their methods of infection (and the means you would use to combat them) are quite, quite different.
There has never been a particularly urgent need to produce a vaccine for the common cold in general - it's a mild, self-limiting disease with extremely low mortality and so the time, money and effort required just can't be justified. When using the older, more normal vaccine platforms, it could to take up to $1 billion dollars and 5 - 15 years to develop a typical vaccine, with as I mentioned before, only a 6% chance of success, on average. And there's even less chance that the money, time and effort could be justified for each of the four different coronaviruses that cause colds, since even taken all together, they only account for around 20 to 30% of cases.
On the other hand though, vaccines
have been developed for the coronaviruses that are most similar to SARS-CoV-2 (SARS and MERS) - they just haven't been fully trialled and implemented, again mainly because the financial incentive wasn't there. SARS died out by itself before a vaccine was fully tested and MERS only kills around 200 people a year in only a few countries so it isn't seen as a massive global threat. One of the more promising candidate vaccines for MERS that has gone through several stages of trials, was developed by the Oxford University and Jenner Institute team including Professor Gilbert.
I've looked up Professor Sarah Gilbert - she seems to be a world-renowned and highly respected vaccinologist with nearly 3 decades of experience in the field of vaccine development and implementation. If she is highly confident of success, it's probably because she has extensive practical knowledge of not just developing vaccines in the lab but actually testing them on people. She has been involved in the development of and clinical tests for, over 50 different vaccines for various diseases in humans. Also as mentioned, her team has already developed a MERS-CoV vaccine which has successfully progressed in all its trial phases so far. So I think if anybody is in a position to know how promising her team's candidate vaccine for SARS-CoV-2 is, then it's her.
See the clip below where she talks about viral vectored vaccines, which is the kind of vaccine that her team is developing for use against SARS-CoV-2.
If you want a further illustration of just what a comprehensive knowledge she has in the field of vaccines, here's another video where she talks about their work on developing an improved flu vaccine that would work against all strains of the flu and wouldn't need to be updated each year. It's a bit long at nearly forty minutes but it's a fascinating lecture (if you're interested in that kind of thing).
