A LOT, like a HUGE part of who wins a race, is tires... probably more than anything else.
Team A gets the good tires, Team B doesn't. Team A wins... every race.
Goodyear likes to point out that every winner of the Daytona 500 was on Goodyear tires.
... well that's because Goodyear sponsors the Daytona and you have to have Goodyear tires to enter the race.
Goodyear, for a long time, couldn't build a short track tire... so some racers, even Goodyear sponsored cars, would paint Goodyear logos on Hoosier tires... and win races.
Goodyear DIDN'T mind... until the press found out and reported it. Soon after Goodyear had a short track tire.
When it gets to the point where you NEED a specific tire to win, they'll sometimes make the tire a spec tire (you have to run a specific tire to enter) to level the playing field.
When I started racing "production" we had a Dunlop as a spec tire. (I hate Dunlops).
The "HOT" setup was to run the rear tire on the front, mounted backward. It was stupid setup... BUT you had to do it if you wanted to win races.
Spec or control tires (or ANY part for that matter) is USUALLY to level the playing field, so that the big buck teams don't get to BUY race wins, by controlling who gets the "good" parts.
Over the years, tires have decided who wins races more than anything else... OK tires and driver talent... but the best driver usually CAN'T win without a winning tire.