In Sitecore, whenever items are synced (bucketing) or sorted, the "updated by" and "updated date" fields of the affected items are updated with the current user.
However, in my business team, these are seemed as trivial operations and so they prefer the "Updated by" and "Updated date" to be unchanged so that these fields show info of the user who did the actual update to the item (like field updates).
Is it possible to achieve this through any means (either by configuration or customisation)?
If you want a field that always holds the last actual update (in terms of a content editor), you should add it yourself and fill it automatically (like on the item save event). The __Updated fields on the Sitecore statistics will be changed whenever the actual item is changed -cannot change this with a simple config- and that can be for several reasons (e.g. also when you would sort items as that can change the value of the standard sort field).
There is probably a way to customize this with code, but it will be a lot easier and less error prone when you create your own field and keep the data there..