The thing about 2020 was it was a splurge to help a rookie QB.... and it did. The problem was you do that on the assumption that while the rest of the team will decline each year as you age or price guys out, the QB will get better and be able to elevate what is left. They were wrong on Mac more than anything, and he completely crumbled the moment the line went from very good to above average... that made a lot of guys worse, then they missed the next year on some swings, draft pick gets hurt, etc. etc. and it snowballed. Their good RG had to play RT, their promising LG got hurt again, their good LT didn't want to be here anymore.... etc.
As to right now... I think we can feel pretty good about interior line next year if Onwenu is moving back inside. He's a very good guard. Sow showed promise both last year and in preseason and amongst him, Robinson, Jordan you feel okay. Center is a concern, but.... if Strange is back at some point he'd make sense there (or at guard), he's been an above average NFL player at times despite injuries.
Tackle is the issue. Could Wallace play RT... I think so, he's a raw mess right now, but he shows the skillset to be solid there with time. Left Tackle needs to be a priority in the draft.