Even then honestly, Mass Effect came our in 2007, Fallout 4 was 2015. Mass Effect was about a specific character that yes you were supposed to be able to shape and mold, but the expectation that the Fallout series had built up was for you to be basically anyone. And to my recollection 4 did nothing to temper that expectation going in with their new dialogue system and voiced protagonist.
Even then honestly, Mass Effect came our in 2007, Fallout 4 was 2015. Mass Effect was about a specific character that yes you were supposed to be able to shape and mold, but the expectation that the Fallout series had built up was for you to be basically anyone. And to my recollection 4 did nothing to temper that expectation going in with their new dialogue system and voiced protagonist.