Nobody wants kids to leave the program and we all appreciate their commitment and effort. At most colleges, 4th year players are not invited back for a 5th year unless you are projected to be a starter or a key backup. Some schools push kids out before they get to the 4th year if they are not projected to be key contributors on the field.
Edsall probably doesn't want all of the kids to leave that are in the portal, but for most, it was time to seek another opportunity. Unfortunately, that is the tough reality of college football. The players that are leaving that were starters may want to try to see if they can play up for their last year. You have to respect that after the losing the past 4 years.
If you look at the 4th year players that are currently in the portal or have announced their departure, here are their stats for 2019:
Beaudry: played 5 games, 53/83 503 yards, 1 TD, 2 int. 2nd on team for pass yards, 3rd for TD passes.
Donaldson: played 10 games, 2 receptions, 30 yards, no TDs. 25 kickoffs. 7th in receptions by WRs.
Brouse: played 0 games
Leone: played 11 games, OL starter
Hahn: played 12 games, 3 tackles. 8th in tackles for LBs,
Gilmartin: played 6 games, 29 tackles, 1 sack, 5th in tackles for LBs.
Garson: played 1 game, no stats
Herring-Wilson: played 8 games, 17 tackles, 1 pass break up. 7th in tackles for DBs.
Coyle: played 11 games, 86 tackles, 1 int., 10 pass breakups. 1st in tackles and pass break ups on team.
Graham: played 11 games, kick holder, no punts.
D. Williams: played 4 games, 5 catches 62 yards. 3rd in receptions for TEs.
Here are the undergrads that appear to be leaving:
Black: played 6 games, 13 carries, 61 yards, 0 TDs, 1 catch, 6 yards. 3rd in rushing yards on team.
Scott: played 4 games, no stats
Carroll: played 0 games. Academic redshirt.
Hubbard: played 3 games, OL backup.
Holmes: played 12 games, OL backup
Out of all the players leaving, 2 were starters. (I did not include DeGeorge as he is not yet in the portal.)