Completely agree - the ability of BRP rules to fade into the background or be used loosely is very strong. For instance, full battles take so much time, I’ve taken to just making single Battle rolls when an encounter doesn’t seem worth all the bells and whistles, and it’s easy to adapt more modern rules design (for instance, I use ”Let it Roll” from Burning Wheel for tracking, sneaking and other ongoing activity, rather than rolling per time period).
RQG is big but loose.