This depends on the reason for the 221g. Security-related reasons can take a while but often 221gs these clear quickly. What's the reason?
The officer told me to send CV, job offer and support letter on email. Even though these were available at the interview so this ask looks to me more like a facade.
I've heard about a person waiting for 4 years for their B-1/2 U.S. visa recently.
I haven't heard a single story where any kind of feedback or realistic timeline was provided to anyone, be it the applicant, the employer, a lawyer, a congressman. Not once.