For some it's more difficult to change gears after doing something else over a period of time. Depending on the amount of time already invested, certain exercises or patterns may be played more fluently by the current method than by changing the program. Timing may also have developed in the method of style in which it's been played.
Incorporating the pinky may help to expand in new aspects and make certain things easier to accomplish.
I don't feel that it makes an extreme difference by how something is played, as long as it's played well. Use what comes natural.
Some players rarely use their pinky finger while soloing, whereas I constantly use it.
Look at Clapton, Rarely a pinky when soloing, but frequently in chord structure.
Zakk Wylde, too....
Relearning a new method in playing guitar is a personal choice. If it's better, do it.
Django Reinhardt worked with two fingers in his new method because he had no other choice...........