The total amount doesn't matter at all, since the drop rates have been buffed so heavily over time. I got like...I don't want to lie, I'm not 100% sure, but like 6 or 7 legendaries since patch 7.2. Just cleared all normal and heroic modes every week (EN, ToV, NH), did a bunch of m+ (like 5-20 per week, depending on affixes), emissary quests every day and received one legendary per week roughly (usually wednesday on reset) since 7.2. Friend of mine is doing the same formula and also has 14 legendaries, gets another one every week
However I was kinda unlucky with legendaries for the most part, sephuz first (the old, slightly shitty version), only got luffa in like march 2017 as 9th legendary, took forever...it's not only about the total amount, but rather how quickly did you get the ones you actually wanted to?