But one thing that Larian did greatly is to make turn-based mainstream again.
cough XCOM 2012 cough
You are spot on there. Perhaps they are thinking turn-based fantasy rpg which has either been RTWP or arcade action-based.
Yes TB never stopped being mainstream. What the D:OS games did was to push studios towards a mindset that TB is now the ONLY way an RPG should be made. So not mainstream but exclusiveness.