To say "fretboard material A always produces tonal characteristic Z significantly" regardless any other factors (neck material, thickness and construction; truss rod design and implementation; headstock; body wood; hardware; pickup location and configuration; electronics; etc. etc.) Is simply ludicrous.
You're all entitled to your opinion of course, but don't try to sell it off as science.
Manufacturers sell products with variations to sell more products. Tapping a block of wood can tell you something about it's density and possible included cracks and faults but it's only one of the checks a piece gets before it's chosen (hydrometer for instance).
Also I might be mistaken to the meaning of the 'fundamental' which in audiology we mostly assume to be the lowest dominant frequency in the timbre. The one frequency that does not fit in the 'maple is brighter' theory as that mainly suggest that the higher frequency overtones become more dominant in the timbre.
Classical orchestra string instruments almost exclusively seem to feature ebony fingerboards yet differ great in tone, something to keep in mind maybe when claiming one type of material always has the same sound.
Lastly, can we refrain from name-calling people with a different opinion? Flat earthers, trumpian fact-deniers or whatever it was. Even more so when your logic is flawed and your facts are cherry picked and incomplete.