BOAC. Yep. I know that it makes it easy to input digital stuff. That's a benefit for a manufacturer, but not to a pilot.
What are the benefits of a SS for a pilot?
The other obvious drawback is that yokes move together. With SS, opposing unputs are possible (I know they have a way of summing them or for one SS to take priority, but how can either of these features benefit the pilot???)
I know the F-16 has a SS, but most F-16 are single seaters and in the two seaters (mostly) one pilot is an IP.
The yoke (OK, why not take digital input from a yoke?) has the benefit of being in clear view and both are linked mechanically.
These features might have helped or even saved 447.