Why have the _beforeTokenTransfer and _afterTokenTransfer functions been removed in the ERC721 standard in v5?

In version v4 we have the following functions for the ERC721:

There are the functions for "to do something" before and after a transfer.

They do not appear in the new v5 version:

If I want to use that functions, which standard should I use?

Now there's only one function _update()

You can override this function and add you logic

Ok, I add my logic without deleting this content you show me or is nenessary to save it?

Other question.
When is this function triggered? Before or after the transfer?