When you sort by tag in v2, your orders are secondarily sorted by order number. This make sense and is good function. When you sort by tags in v3, your orders are sorted by that specific tag however they are in a completely random order. Not by age, order number, etc. There is no rhyme or reason to the sort.
v3 should be an upgrade over v2, this functionality should be easy to implement. There isn’t a use case where the current set up is beneficial in any way.