The B1 was a mess, and it got turned into a political football by Reagan. Carter canceled it for two reasons: first, the USSR upgraded the radars on their intercepters in a way that made the "nap of the earth" bombing mission suicidal, and second, he know about the B2 program. Reagan was briefed on the B2 and knew the B1 cancelation was the right decision, but decided to use it to portray himself as "tough" vs the USSR, making restarting the B1 program one of his big campaign promises.

Here's the AF's current thinking, all be it in a memo with let's say, unexpected formatting: https://www.af.mil/Portals/1/documents/2020SAF/There_Is_No_S...

The tl;dr is the AF most definitely wants to dramatically change how these programs work, primarily around shorter timelines, less vendor locking, and the AF owning the system integration.