All things being equal (litteraly i suppose in this case
), as with engines, customer car teams would rarely win, the best drivers would still want to race for the factory team, and when the occasional pink merc or rosso bull customer car wins its under a highly rare set of circumstance and most will be thrilled when it does because who doesnt like rare things.
It wont become like Indy car because Indy car only costs between 10-20 per car per season.
Williams, a poorer team, alone can afford to field half the current Indy grid with their current budget. Merc could field like 50 Indy cars if they wanted.
Even with the soon to be budget cap, F1 cars, customers or not, are still going to be very very expensive pieces of kit with team capable of spending on areas to differentiate themselves from each other.
While i dont see the need to get rid of the constructors, i can see the point Casper is making and it speaks to making this about driving, about putting the focus back on drivers...personally i like that philosophy.