It's fundamentally about need. If +4 dBu balanced was always audibly better than -10 dBV unbalanced, we wouldn't have expensive audiophile gear with RCA connectors, like we've had for decades. Yes, we get green markers for CDs, and speaker cable risers, yet unbalanced is fine—that tells you all you need to know.
Recording studios often route signals over significant distances (control room to live room), and with a lot of AC cords and other noise-producers. And when a mic gets to the mic preamp, it may go to an optical compressor/limiter, then an outboard EQ, then a FET compressor, then a mixing console. From there, after passing through filters that may give additional gain to some frequencies, and out to a bus compressor, and out to the active front monitors over another cable run.
Now...imagine hearing some hum or static. And trying to find at which cable run the noise might have crept in. While the client is sitting there watching his bank account drain.
In other words, whether you can hear it or not, your studio needs to stack the odds towards the signal making it through all those interconnects intact. Balanced helps that bet.
But even in a studio, many connections are unbalanced. Most keyboards, for instance. But if you plug one in and get noise, you'll try another cbale—because you know the rest of the chain is reliable. (Historically, most gear would be semi-permanently wired to a patch bay, where they would get routed. That way, you're always dealing with jacks and plugs that were meant for a lot of abuse, and you'd just buff any tarnish off occasionally.)
I'm in my office + home studio, a lot of things are balanced, a lot aren't. And it's more important some places than others. I have a Topping DAC for listening at the computer, feeding a pair of iLoud MTMs over 1-meter balanced cables. Because the Topping has balanced outputs, and the monitors have balanced inputs, and because I have a stock of Neutrik XLR connectors and Mogami cable—plus, it would be more work to cable it from the RCA outs of the Topping to the phone jack ins of the MTMs (I have the plugs, but they're harder to put on star-quad cable than XLRs). So, I like having the balanced outs, but audibly there will be no difference, short of the unlikely need of an absurdly long cable run to another room.