Relative to the Chicago-land area, the small school competition in the state of Illinois has been really bad the past 15 or so years - the talent just isn't there
I'm not sure what you are implying here but small school football in the state tends to be dominated by non-Chicago-land teams. Here are the qualifying schools for the state championships from the three smaller football divisions this past year:
CLASS 3A
(8) Wilmington 37, (1) Farmington 12
(5) IC Catholic 29, (4) Peotone 16
(2) Williamsville 45, (7) Bloomington Central 14
(3) Byron 21, (6) Monticello 20
(16) Pleasant Plains 29, (8) Newton 27
(5) Carlinville 40, (4) St. Teresa 36
(15) Vandalia 27, (10) Greenville 14
(3) Anna-Jonesboro 29, (6) Pana 14
CLASS 2A
(1) Newman Central Catholic 41, (8) Hope Academy 22
(4) Orion 24, (5) Clifton Central 21
(2) Gibson City 24, (10) West Carroll 6
(14) El Paso 28, (6) Knoxville 22
(1) West Hancock 28, (8) Bismarck 12
(4) Maroa-Forsyth 48, (5) Eldorado 6
(2) Westville 46, (10) Carlyle 28
(6) Shelbyville 50, (3) Tri-Valley 35
CLASS 1A
(1) Lena-Winslow 49, (8) Milledgeville 16
(5) Aquin 21, (4) Stockton 14
(10) Princeville 21, (2) Wethersfield 20
(3) Forreston 30, (11) Fulton 6
(1) Tuscola 50, (9) Brown County 13
(4) Carrollton 20, (5) Camp Point Central 18
(2) Red Hill 36, (10) Cumberland 0
(6) Athens 42, (3) Argenta-Oreana 12
Now, if you are saying that the majority of Div I talent in the state plays for the larger schools in the state then I will agree.