There are plenty of times that the FP+ and standby waits are exactly the same. A FP for most WDW shows is effectively the same as waiting standby.
Nor is it always the case that FP = a shorter wait time. In some cases, the standby can even be faster, because standby riders don't have to scan their band. I can think of a number of rides where this happens, especially early/late in the day, or whenever a ride reopens after a mid-day shut down.
Most of the Epcot FP's are effectively no different than standby: Pixar films, Imagination, Living with the Land, Mission: Space Green, Nemo, Turtle Talk, and sometimes SE. If there is any difference at all, it is negligible (under 5 minutes).
I don't ever recall seeing any of the following at anywhere near 75 minute waits since they became FP+ attractions, even mid-afternoon on peak holiday weeks: Barnstormer, Dumbo, Small World, teacups, Aladdin, Philharmagic, Monsters, LM, Muppets, VoLM, or the live bird show. Dumbo and LM had maybe 30mmin waits when New Fantasyland was new.