I flew a 260 many years ago. It is a fine aircraft.
I recall there is a wide margin between the takeoff speed and the flapless stall speed hence (as you take off with take-off flap set) if you retract the flaps too soon after takeoff, you will stall and die for the reasons stated in the OP.
Surely it was a different designer who came up with their 4 seat alternative to the PA-28?