It's pretty simple, really. The Steelers have more money to spend in free agency because Ben is no longer commanding a monumental salary at the quarterback position. The contract he signed in 2020 (2 years for $68 million) at his advanced age severely handicapped them. Sure, he took a five million dollar pay cut last season when restructuring, but he still cost the Steelers $26 million against the cap last year, plus another $10.3 in dead cap in 2022. Trubisky is costing a fraction of that, so they can address other areas of need.
Levi Wallace is a solid signing. Very encouraged with what they're doing so far this offseason.