Benefits:

• Fast context switch (browsing, editing, documentation, etc).
• Fast grouping(again browsing and all).
• Automatic grouping (one can set rules were opens were)
• It is even more useful on single monitors, the little space one has means that usually on can split the screen no more than 2 times, this means that swtiching quickly between groups of windows save you a load of time.
• On the long run one gets used to the workflow and the cognitive effort of moving around windows becomes super low.

Cons:

• Might take some cognitive effort getting used to the workflow/keybinds. (usually worth it in the long run)
• Moving around windows or workspaces can be difficult if not setup up correctly.

One step further

Tags (as opposed of workspaces/virtual-desktops) are a system used by the likes of dwm, dwl, river, mangowc to choose what windows get displayed on the screen. This would allow you to toggle and view different groups of windows on the same screen(like viewing multiple virtual-desktops at the same time). This would allow one to do that super fast context switching at a more complex level if needed. For instance you could toggle the "tag 2" while viewing "tag 1" effectively merging the two tags into the same screen instead of switching back and forth with workspaces. This method requires a little of more focus and remembering the state of the windows/tags.

Quick mention of my Window Managers if anyone is interested in the topic.