The people's choice is unique compared with the BGG top 100 in that heavy games drop off fast after a couple years in favor of whatever the new hotness is.
You can see 5-10 year old high-ranked heavy games like War of the Ring, Mage Knight, Eclipse, etc disappear from the people's choice and get replaced with Scythe, Gloomhaven, and Terraforming Mars. Even the #3 rated Through the Ages is dropping off soon. This is in contrast with BGG where those older heavy games tend to stick around in the top 100 for years and years