The game has changed from the old wooden racquet era. Next was graphite composite racquets. Then stronger and stronger players. Followed by more and more topspin (unfortunately from further and further behind the baseline).

The next era in our game's development occurs from the new "copoly" strings - essentially a polymer material, but somehow little or no friction between the strings.

You will note, no longer do the players walk around between points straightening their strings. That is because those strings move back and forth when meeting the ball - imparting much much more spin.