You forgot to mention that these diseases can also kill.
The number of measles cases has climbed to the point where it is a statistical wonder that we haven’t heard about any deaths yet. Measles kills about 1 in 500 immediately; another 1 in 1,000 die several years later from a recurrence of measles in the brain.
Rigorous vaccine programs have brought the worldwide measles annual death rate to fewer than 100,000. But only a couple of decades ago, annual deaths were counted in the millions.
Rubella kills and maims the very young, those who have not been born yet.
These diseases are not like mild bouts of the common cold. They are serious; this is why vaccines were developed. No one has bothered trying to develop common cold vaccines, because deaths from the common cold are extremely rare, if they happen at all.