Michigan's OL might actually be better in 2023...
They'll have 4 of their top 6 OL's back. LG Trevor Keegan, RG Zak Zinter, T/G Karsen Barnhart, and RT Trente Jones. Jones was the starting RT until he got hurt and Karsen Barnhart started a majority of the games in his place. Then they added three veteran OLs in the transfer portal in LaDarius Henderson, Drake Nugent, and Myles Hinton. Henderson was rated a 4* and the #2 rated interior OL in the 247 Transfer Portal rankings and is a talented vet with 29 games of starting experience under his belt, Nugent was PFF's fifth highest graded center in 2022 with an 80.5 grade- PFF rated him as the #6 returning interior OL for the 2023 season, and Myles Hinton who is a former 5* 'croot and a mountain of a human being at 6'7, 315+ lbs.
Then they have returning in their two deep RS Soph's Giovanni El-Hadi (4*, top 100) and Raheem Anderson (4*, top 200) who made waves in spring/fall last year as rs frosh and in spring this year. Then they have RS Frosh OT Andrew Gentry (4*, top 100) and true frosh G/C Amir Herring (4*, top 300) who has already made noise in spring and is said to be a starter in waiting.
They'll have more talent and depth along the OL than they've had at any time in the Harbaugh era. Ryan Hayes can be replaced, he was a solid player at LT but nothing unique or special. Olu Oluwatimi will be a big loss at center, and he was a special player- but Drake Nugent is no slouch as a fill-in and they have a lot of experience, talent, and depth returning.
Will there be a better OL group in the nation in '23 returning? I don't know. Will there be a better 1-2 punch at RB in the nation in '23 returning than Corum & Edwards? I tend to think not. Corum is a special back and Edwards is even more special imo.