Of course! Because when you have a ride that was a 5 min standby, like GMR, Figment, Nemo, etc, and then you add in a FP+ line, now that 5 minute standby turns into a 10 or 15 minute standby because the FP line will be taken before the standby line.
I saw this with GMR in February. We didn't wait long, overall, but waited longer than normal. All while people were going through the FP+ line.

I don't get FPing rides like this. But people are going to do it, which will make the standby line for those rides longer. Maybe only 5 or 10 minutes, but it's 5 or 10 minutes longer that it doesn't need to be.
Case in point the thread yesterday or the day before where the OP just decided to go to Epcot and picked Nemo and Figment as two of her FPs.