There is a bit of truth in your saying here.
As our boards are made of metal there is very often a metallic tint that can be heard while typing.
And this mod nearly eliminates this metallc tint, so in that sense it kinda uniformize how a board sounds.
So if your preference is to be able to hear this subtle tint of metal ringing while typing, don’t do this mod.
Howerer this is the only thing that this mod changes.
It does not change the sound pitch so everything that can effect the pitch, plate material, case material, amount of space between the PCB and the bottom case, stays untouched.
And this is what I like in this mod.
Not a sound expert,but I think that the amount of ringing is exarcerbed with a more roomy space between PCB and bottom case
Whitout ringin you’d end up with a boomy (are rather noisy) sound while typing, quite enjoyable (not much for your neighbours;) ) and this is what you ended up with using this mod I think.
Some designers like @Jae-3soteric with the J01 explicitly added an acoustical chamber in the bottom case to emphasize this boomy sound experience.