It’s definitely real, but it’s usually an add-on service! 🎶 Most gondoliers don't sing unless it's a specific Serenade
tour. You usually have a singer and a musician join you in the boat (or in a nearby boat in a group). It is incredibly romantic and the acoustics in the narrow canals are amazing.
I'd recommend looking at the Serenade
packages under Gondola Rides in Venice https://alle.travel/en/venice/category/gondola to make sure you get exactly what you're looking for. It does cost more than a standard ride, but for a special occasion, it's 100% worth it.
Just be prepared for people on the bridges to stop and watch you - you'll feel like a celebrity!