Actually the logic behind this is very understandable and consistent...

Sky diving, traffic watch, pipeline patrol, game tracking, repositioning, etc do not involve carriage of innocent members of the general public. Under most circumstances flying the public requires a 135 or 121 certificate, but the legal wording requires carriage from point A to point B to trigger 135/121 requirements. Basically sightseeing used a loophole in that it went from point A back to point A (sightseeing from point A to B was never allowed...this is considered on-demand flying).

So really they are just raising the bar for pilots carrying the innocent public, to make it a little closer to 135 mins.