This is besides the more obvious answer to your stupid question, which is that squats and deadlifts isolate the lower body and bench the upper body. Real-life exercises like sprinting, tennis and boxing use the entire body all at the same time.
Wiggins, normally i like your stuff, but this is just plain wrong. If you're using machines to squat or work pecs, then yes, almost pure isolation, but just try doing free weight deep squats with 1.5-2.0X bodyweight and you will be working calve, quads, major glut work, lower back, core, and yes, even my arms are tired, it's not easy stabilizing/balancing that much weight! As other poster mentioned, proper BP requires strong gluteal contraction and upper body stabilization.
But it goes way beyond getting strong, these multi joint exercises stimulate GH and T, which has systemic effects, not localized to the purported "isolated" muscles. More crucially, there are many studies on aging runners and non runners alike where these basic exercises improve running, general day to day functionality, even reducing falls and fractures
Will it help your sprinting, clearly.
Will it help your 10k? Salazar thinks so, he has Rupp and Farah doing a lot of free weight work including squats. Should it be the core/primary part of a runners program? Of course not, distance, intervals, tempos, strides and hill work are key, but as an adjunct, especially for those in the 40+, esp 50+, it can be a benefit to running and general life activities.