bridger responds:

it's more of a can of worms than you might realize.

first, the veneer on plywood is very thin. it'll get torn up right
away if you walk on it.

Way too thin.

second, the regs on stairs are pretty tight. you are *not* allowed to
just go randomly changing the rise...

Not really regs, but stairs need to be almost dead even in size. Any
significant (over 1/4" or less) variation causes tripping.

Basic solution: find a carpet you like better.

By the way, I tend to doubt the stair treads themselves are OSB. Possibly
plywood, though even that is a rotten choice.

Charlie Self
"Bore, n.: A person who talks when you wish him to listen." Ambrose Bierce, The
Devil's Dictionary