Are Warrant Officers Really Officers?

In the US military they're definitely officers. On base they'll get officer's quarters, and they can go to the officer's club.

Warrant Officers's are technical experts in a given military discipline, e.g., artillery, helicopter pilots, air defense, counter-intelligence, IT and many others. In the US Army there are about 45 Warrant Officer MOS's (military occupation specialties):
https://recruiting.army.mil/ISO/AWOR/ARMY_FEEDER/

WO's occupy a niche between noncommissioned officers and commissioned officers. They don't command troops as a rule (though in certain instances they can) but due to their subject matter expertise are very important as technical advisors to commissioned officers, and as trainers to the enlisted ranks.

The WO cohort commands a high degree of military esteem; and though they are theoretically outranked by all commissioned officers they have a status equivalence which roughly parallels that of the commissioned officers: A WO1 being somewhat akin to a 1st Lieutenant., a CW2 being somewhat equivalent to a Captain, a CW3 to a Major, a CW4 to a Lieutenant Colonel, and a CW5 to a Colonel.

WO's are often older soldiers - in their thirties or forties, fifties even - who climbed up the ranks for many years as enlisted men and women before their elevation to WO; thus they've been in the military a long time and know how things there work. Because of their knowledge, technical expertise and insider information officers respect them, but don't really know what to think of them. NCO's see them as officers and stay out of their way. And the junior enlisted soldiers love them because they're chill with them. In the Army at least they are an entity unto themselves and as a rule no one messes with them because they're outside the normal chain of command.

CW5's, the highest of the WO ranks, are a rare sight. They're called "unicorns" because it's very unlikely you'll ever see one in the flesh, and are said to emanate a mysterious, almost god-like aura.

Fitz