Biden’s aggregate lead is higher currently than any lead Hillary ever had. He’s up by almost 10 percent in aggregate polling (6 points higher than Clinton was four months before the 2016 election), leads in state polling for electoral college at 368 total electors (need 270 to win), the tipping point state per 538 at this point (state that would determine winner if each candidate held their respective current blue/red state polling averages) would be Florida - a state Biden leads by 7.2 percent in aggregate polling, Biden also leads Donald by at least 4.5 percent in polls in seven states that lean R generally and Donald would have to win all of simply to even reach Florida as a tipping point state, and several states that Donald won in the Midwest in 2016 are democratic leaning overall while Donald won them by under 1.5% each.
So TLDR; yes Hillary led in polling leading up to the 2016 election (but within the MOE- I believe 538 gave Donald a roughly 1 in 4 shot to win Election Day. Put another way, the same odds that if you flip a coin twice in a row you get heads both times) but the underlying context of states Biden leads plus the lead that he currently has (around 3x as big as Clinton’s Election Day polling lead) suggests that if the election were today Biden would be a very very heavy favorite.