In this case it is. High capacity 7200 rpm drives can be unbelievably noisy, to the level that they are not recommended for home theatre NAS as you can hear the seeking sound during a movie or from the next room at night.
That's not true. Even a spinning sound of a 5400 rpm disk makes quite loud.
Whether you can hear it due to casing or distance is another matter. Most of the time fan noise will make you ignore it. When fan is not spinning I can hear laptop drives clearly.
Synology forums have several threads like this: https://community.synology.com/enu/forum/1/post/130843
And I understand that these are different companies, but why I even went for Seagate was because of the CMR issues.