Pretty sure it makes a difference, but not sure if it would be noticeable by most. Tons of videos out there to get you close, then it time, trial & error, and throwing $ at parts to get you closer. Probably the biggest advantage I see is it could save you some cash in parts swapping and time…….
again I’ve never experienced a fitting, but I wouldn’t think it would be a huge difference. Once you get the initial bike size right, seat right(height, angle, for and aft) most everything else makes minimal difference to me.