@LemuelGuliver had an IMO great question lurking in https://travel.stackexchange.com/questions/81493/how-to-get-to-cairo-from-boston -- how can you search for flights staying within an alliance? His question was using his status, well, that's the point of an alliance, your status will be recognized to some extent.
ITA Matrix can do this using the
/ alliance limiter, there's
oneworld. To give an example I used the original question as parameters -- I couldn't find anything direct so I asked for one connection:
This particular one will correctly find flights on British Airways and Qatar.