I actually know someone who has some insight into the league through official channels, and he said they considered the bubbles, but realized it was unsustainable with how many daily games needed to be played.
If they do the bubble after a reset, I see it being more of a tourney than a season at that point.
EDIT: Personally, I think the bubbles were a no go the second they realized only four to six Primetime games could be on a night. At the end of the day, with no one in the stands, it’s about ratings/ad revenue.