The Fed bought the most T-bills during major QE programs:
2008-2014: Peak crisis response, bought ~$3.5T total
2020-2022: COVID response, added ~$4.5T to balance sheet
March 2020 was insane - they were buying $75B+ per DAY at one point. Made 2008 look quaint.
The proposed $40B/month for 2026? That's actually pretty tame compared to crisis levels. Either they're being cautious or something big is coming.