Can the 2020 GMC Canyon make a U-turn?

No. Needs more than 40 ft.

41.3ft curb to curb

Street width, feet

Street 40 feet curb to curb.

2020 GMC Canyon 2WD Ext Cab 128" SL. Top view, to scale.

2020 GMC Canyon: turning circle by trim, 40 ft street
Trim	Circle, ft	Margin	One move
2WD Ext Cab 128" SL	41.3	-1.3 ft	No
SL Extended Cab RWD	44.6	-4.6 ft	No
2WD Ext Cab 128"	41.3	-1.3 ft	No
Extended Cab RWD	44.6	-4.6 ft	No
Crew Cab RWD	41.3	-1.3 ft	No
2WD Ext Cab 128" SLE	41.3	-1.3 ft	No
SLE Extended Cab RWD	44.6	-4.6 ft	No
SLE Crew Cab RWD	41.3	-1.3 ft	No
4WD Ext Cab 128"	41.3	-1.3 ft	No
Extended Cab 4WD	44.6	-4.6 ft	No
4WD Ext Cab 128" SLE	41.3	-1.3 ft	No
SLE Extended Cab 4WD	44.6	-4.6 ft	No
SLT Crew Cab RWD	41.3	-1.3 ft	No
SLE Crew Cab 4WD	41.3	-1.3 ft	No
4WD Ext Cab 128" All Terrain w/Cloth	41.3	-1.3 ft	No
All Terrain Extended Cab LB 4WD	44.6	-4.6 ft	No
SLE Crew Cab LB 4WD	44.6	-4.6 ft	No
All Terrain Crew Cab 4WD with Cloth	41.3	-1.3 ft	No
4WD Crew Cab 141" All Terrain w/Cloth	44.6	-4.6 ft	No
All Terrain Crew Cab 4WD with Leather	41.3	-1.3 ft	No
SLT Crew Cab 4WD	41.3	-1.3 ft	No
4WD Crew Cab 141" All Terrain w/Leather	44.6	-4.6 ft	No
SLT Crew Cab LB 4WD	44.6	-4.6 ft	No
Denali Crew Cab RWD	41.3	-1.3 ft	No
Denali Crew Cab 4WD	41.3	-1.3 ft	No
Denali Crew Cab LB 4WD	44.6	-4.6 ft	No
Crew Cab All Terrain 5 ft 4WD	41.3	-1.3 ft	No
Crew Cab All Terrain 6 ft 4WD	44.6	-4.6 ft	No
Extended Cab 6 ft 2WD	41.3	-1.3 ft	No
Extended Cab All Terrain 6 ft 4WD	41.3	-1.3 ft	No
Extended Cab SL 6 ft 2WD	41.3	-1.3 ft	No
Extended Cab SLE 6 ft 2WD	41.3	-1.3 ft	No

What this cannot tell you

Curb-to-curb turning circle as listed.

Mirrors and overhang need more room.