Biggest problem is the bad press for the clips whether gator or the other styles. Whether they are for driving agri equipment at shows or driving the ventilating fans in old school building. Some buildings had flat leather belting 8 inch wide barrage cemented overlapped shaved ends. still in use in the mid 90's when I retired in Detroit.
People would get their hands and fingers hung up on the clips and ripped up, when they would try to see if the belting was running to hot or if the slack was to much. Due to stretching and atmospheric conditions.
Besides gluing was easier to do right the first time if the length was correct.
Just a side note on round leather belts.
Here are some types that can be used and the clips used to secure them along with the tool for the leather belts



In the US it is still used on food equipment and some industrial sewing machines. But as with most things when in doubt McMaster-Carr