You can still do a time based release without jumping major versions so often. Eg. OpenBSD's version number increments by 0.1 every six months and has done that for more than 20 years.
It makes sense. Version numbers should be intuitive. Constantly changing software should update by whole numbers, so that the more it has changed, the more the number is different. Whereas "3.11" seems almost identical to "3.86" because they're both based on 3.
Although I would argue that it should change by 0.5 per feature or something like that, so that if it has 10 new features the version number will be 5 higher, but only 2 new features will be 1 higher. Because Java has changed very little from 8 to 12, whereas Firefox's last 4 changes were altogether bigger.
So there is no notion of big or small releases. Hence the seemingly fast increase of version numbers.