It's quite simple really. There are members on here of (and above) a certain age. During their formative years, in the music they were listening to, bass guitars often sounded like a dull thud due to the recording technology of the time. This is what they grew up with, the sound of their youth, and what they aspired to. So fast forward to now, how do you make a bass guitar sound like a dull thud? Flats! 😆