The tenacity up from Rex, and Chirrut now becomes a very significant disadvantage. Rebels who debuff under Luke will be giving TM like crazy. Chirrut less so, because he only gives tenacity up if no debuffs were removed. So this leader ability seems solidly aimed at countering Rex. And I believe it will.
Secondly, AoE characters will have to think twice about using that ability. Luke, Fulcrum, Wedge, Biggs, R2, and potentially Leia all have very nasty damage or debuffs on basics. Now the AoE speed meta is past, but the most used AoE character at the moment is Nihilus. His AoE could get either him, or his taunted killed against a Luke team.
So I think that all current meta teams will hang around, but we will not only see some new teams with commander Luke, but some other new teams meant to deal with him.