I think you might be over-reacting a bit.
The Steelers had one of the worst rush defenses by any measure in 2021. They have shored that up a great deal in 2022. In the past two weeks they have faced the #3 and #4 rushing offenses in the NFL. And it has looked not good. Considering where they came from, it is still a whole lot better than many expected. They have a long way to go to where they want to get to -- #1 rush defense in the league. But that takes more than one off-season likely.
For instance, in 1998 the team was 13th in rush yards on defense. In 1999 they were 26th in rush yards on defense. In 2000, they were 12th and in 2001 they were finally #1 again.
Can we stop with the emotional revision of history into a whole bunch of things that never happened?
The current team was 32nd last season and they are currently 15th. Keep improving and they should be better next season as well.