I expect
@HoopsTournament will answer your question with an udpate.
This is headed toward the chalkiest Sweet 16 I can recall (UH/A&M still in contention; SDSU/Yale lopsided, but still in first half).
The only times that all #1 and #2 have advanced to the Sweet Sixteen are 1989, 1995, 2009 and 2019 (and very soon 2024)
The lowest sum of seeds is 49 (in 2009 and 2019). If Both games hold, the sum of seeds this year will be 53 (if I did my math right). NC State is keeping it from being the chalkiest.
There will be 14 teams from the 6 Power conferences (Gonzaga and San Diego State are the exceptions). 2016 and 2017 had 15 teams. And 14 teams have happened a handful of times.