An early Swordfish would displace less capable naval aircraft

If the Swordfish had been available earlier, would Britain still adopt its predecessors?

No. A service would operate the more capable aircraft and direct development toward something better, rather than buy contemporaneous inferior types.

A navy would have little reason to select a Blackburn Shark or Seal if it already had the better Swordfish in service. Earlier availability would change the comparison set for every competing type. The next objective would be an aircraft superior to Swordfish rather than a lesser replacement.