Could airliners fetch data like AoA and speed from an INS?
An INS gives your speed &amp; orientation in space, but without reference to what the airmass that you're flying in is doing.
The Pitot tube and AOA sensors give speed and pitch orientation in relation to the local airmass, only.
An indicated airspeed of 60 knots, measured by the Pitot tube, may correspond to a stationary aircraft pointed into 60 knots of wind, or an aircraft moving 30 knots over the ground into a 30 knot headwind, or 60 knots of groundspeed in still air, or some other case.  The wings fly (and stall) relative to the air, not the ground, so measurements of air data are vital.