It took winning an Emmy for Lena Waithe to prove there was room in Hollywood for stories like hers.

Three years later — and given the dozen-plus TV and film credits she has racked up since — the biggest question is: Why was there ever any doubt?

“There’s a sea of us,” Waithe said in a phone interview last month. “There’s so many of us out there and people just act like we don’t exist.”

True as that may be, there seems little danger now that anyone could overlook Waithe herself, who since winning that Emmy has been attached to one high-profile project after another. But about a decade ago, when she was first trying to make it as a queer writer of color, her personal story was a tougher sell.

In that light, her new semi-autobiographical series, “Twenties,” which debuts Tuesday on BET, isn’t only the fruition of a dream several times deferred. It also underscores how much has changed since she first tried to get the series made.