Does "Not Accepted" Affect My Adobe Stock Account?

There is no particular rejection rate target posted by Adobe, though it is generally assumed by the community that having an acceptance rate of less than 50% could put your account in jeopardy.

Basically, just a statistic to give you incentive to improve. 80-90% and up is a good acceptance ratio to aim for. Anything less than 50% might hurt, but I've personally never heard of no one having their account suspended for this reason, unless spamming or submitting too many duplicate assets was the cause.