Let's dive into the data a little bit - first, here are the dual meet standings from Big 10 this past season (2021-2022):
Penn State 8-0
Iowa 7-1
Michigan 7-1
Wisconsin 6-2
Ohio State 5-3
Michigan State 4-4
Purdue 4-4
Northwestern 4-4
Rutgers 3-5
Nebraska 3-5
Minnesota 3-5
Illinois 1-7
Indiana 1-7
Maryland 0-8
I am going to classify Penn State, Iowa and Michigan as "ELITE". I think Ohio State will join this group in the next year or two based on their recruiting class. These are teams that will only likely lose to each other. Wisconsin was up there with only 2 losses this year but guess what - they didn't wrestle against either Michigan or Penn State.
Let's look at losses by the other teams / with losing margin, and discard losses versus the 3 Elite teams:
Wisconsin - Nebraska (10)
Ohio State - only losses were to Elite 3
Michigan State - Ohio State (13), Northwestern (8)
Purdue - Michigan State (1), Wisconsin (11), Northwestern (5)
Northwestern - Wisconsin (4), Minnesota (22), Nebraska (11)
Rutgers - Wisconsin (5), Michigan State (3), Ohio State (5)
Nebraska - Purdue (3), Minnesota (6)
Minnesota - Wisconsin (6), Purdue (4), Ohio State (10)
Illinois - Rutgers (8), Purdue (12), Northwestern (13), Minnesota (10), Wisconsin (22), Nebraska (12)
Indiana - Rutgers (12), Michigan State (2), Purdue (1), Illinois (33), Ohio State (31)
Maryland - Indiana (14), Ohio State (35), Wisconsin (35), Michigan State (23), Northwestern (22), Rutgers (18)
What I take away from this is that the Big10's lower teams are all capable of winning, but are sometimes also hit by a tough schedule and some very narrow losses. Indiana had a couple of close losses early on - then once Washington went out of the lineup they seemed to fold in the later part of their season. Nebraska went 3-5 but could have easily been 5-3. Several of Purdue's wins were close (by 3, 4, 1)
I don't know what the answer is for IU - but I don't think they are far off from a shot at the middle of the Big10 depending on their schedule. As for wrestlers leaving - it could be blamed on coaching staff, but there are so many other factors (academics, social/personal, results versus expectations) that could also lead to these young people deciding there may be greener pastures elsewhere.