Where did you get those usage stats from?Why is Lando-I being suspected when its usage is only 10%, while Lando-T has 30% usage? If it was breaking the metagame, then why does only 1 in 10 teams use it?
Anyways, Landorus-I is being suspect tested because of its versatility, the ability to function well vs most play styles, its excellent coverage and access to utility moves in Knock Off and Rock Slide allowing it to bypass a few checks. Also, sheer force+LO hits very hard