This is the key.
Vaccine makers are not engaged in rocket science. Making a vaccine to combat a known genome signature is not difficult. Note how many different countries have done it.
The fact that Moderna is talking about modifying their vax makes it pretty clear they know current vax won’t work against the Omicron genome signature.
So why in hell should one get boosted against a virus strain that clearly requires a vax update? Especially if it is aggressive as it appears to be and will replace all current strains in a few weeks.