LEONARD GREENE: Keechant Sewell resignation shows that as long as Eric Adams is NYC mayor, there’s only one NYPD commissioner — Eric Adams

Keechant Sewell, the first woman to become police commissioner in New York City, abruptly resigned last week, and the announcement has set off all sorts of speculation and palace intrigue.

But if this is a story about chain of command and who reports to whom, New Yorkers don’t really care.

If it’s a story about micromanagement at City Hall and how it frustrated Sewell as she tried to do an almost impossible job, these same New Yorkers still don’t care.

Now, if this is about how a strong, determined Black woman broke the glass ceiling only to be marginalized by the old boys network, that is a different story.

Sadly, New Yorkers don’t care about that either.

Until a commuter in the Bronx can walk on the subway platform without fear of getting pushed on the tracks, or until a mother in Brooklyn can let her daughter walk home from school without fear that she’ll be shot by a stray bullet, the cast of characters at 1 Police Plaza is no more important than the lineup on “Law & Order” or “CSI: Miami.”

“I have always strived to bring you and your officers closer,” Sewell said in a farewell letter to New Yorkers. “I believe we have charted a course and implemented initiatives that will have a lasting impact on that relationship.”

Nice words, but the truth is that unless your name is Bill Bratton, Ray Kelly or Theodore Roosevelt, no one is going to remember who’s running the show.

Sewell had to know what she was walking into before she accepted the job. As long as Eric Adams is the mayor of New York City, there is only going to be one police commissioner.

His name is Eric Adams.

Adams, a retired police captain, installed as his deputy mayor Philip Banks, a former NYPD chief of department

“If you don’t inspect what you expect it’s all suspect,” Adams said last week, repeating one of his common refrains. “Some people would say it’s a management problem. I don’t. Listen, I’m going to work harder than every New Yorker in this city to get the product that we deserve.”

As for Sewell, she should have been a law enforcement rock star after breaking barriers on the biggest stage there is.

But Sewell took the humble approach, always giving credit to the cops she commanded — and the public they serve.

Sewell seemed much like TV’s Regina Heywood, the innovative deputy inspector who commands a tough Brooklyn precinct in the CBS drama “East New York.”

Despite her success, Heywood butts heads with a series of higher-level men, including an ambitious deputy mayor who’d like to take the “deputy” out of his title.

Heywood has one more important thing in common with Sewell. “East New York,” despite its loyal following, has been canceled by the network.

She’s not coming back either.