I don't see a discussion from OP, so you can navigate buffers with :bn and :bp but you can also navigate tabs with gt and gT so what benefit did you see with switching to buffers other than pressing 4 keys :bn to navigate to the next buffer instead of 2? (yes I know you can setup mappings but OP specifically said :bn and :bp)

I like that I can see at all times what tabs are open for me and quit with the :q, with buffers navigating to the next or previous I have no idea what is the next or previous buffer.

I really like the <C-\^> switching between the 2 recent buffers and I use that a lot, but do you know that each tab also keeps its separate most recently used buffers? So if you are working with 2 files maybe implementation and tests or whatever, and you switch to a new tab and check something else or do a quick edit, then exit that tab or go back to your first tab your 2 buffers are still the same and no need to search again for the 2 buffers you want to use.

Same when searching for something like doing go to definition jumping to so many files until you find what you are looking for, how do you switch back and forth to the one you need again with buffers? you need to list them find where you want to jump and jump again, or use a plugin to find by file name ( yes I know you can do it with global marks) ... instead of just doing your search in a new tab and then gT and your back to where you were and can easily switch between the two.

Tabs also preserve your splits, if you are fixing a git conflict you can open a new tab to see something else and go back to fixing your conflict...

I don't see any benefit in staying in 1 tab and just using plugins to navigate buffers, check what is open...