Since 1.14 Pre-release 2 (Note: this is not related to the camera pivot, that was removed in a completely different version) the camera view no longer makes a subtle "bobbing" when you jump or fly downwards/upwards, which made the vertical movement feel more natural. This is very likely to be unintended, as it didn't appear in the changelog or any bug fix for that version (not even in the wiki).

Two videos have been attached showing the effect before and after its disappearance in 1.14 Pre-release 2, also here is the link to the official changelog at minecraft.net.