Well, I am focusing more when there are several teams working on the same product. In such case, it is difficult to assign one single semantic versioning when each feature is advancing at different speeds, with several deliveries by day. In those scenarios, assigning just one semantic version, makes more sense as commercial department than engineering. But of course, in smaller products, with small a team, time to time, having a milestone is a good idea. But even libraries like react that continuously release beta versions, only make one semantic version increase every once in a while. (Yet, I am sure that it is hard to know what is in each React "alpha/beta" version each time)

So, as in everything, it is a matter of looking for the purpose and balance.