I couldn't care less about how wood "sounds" on an electric bass, because it doesn't "sound" like anything. The pickups have a magnetic field. The strings are ferris metal. The sound is made by the metal strings vibrating within and fluctuating the magnetic field, which generates a current through the coil,....which is then sent to the amp to be amplified and the reverse happens with the coil in the speaker. Which vibrates the cone, the air and sends sound waves to your ears. At no point are you listening to wood, or is the wood generating sound, or is the pickup sensing vibrations through the wood. It doesn't work anything like a violin or acoustic guitar.
I start with wood that I know is structurally desirable to build the frame that holds the strings. Hardness, flexibility, strength:weight, grain orientation, movement in service, etc. Once I know that the wood is structurally up to the task, I worry about looks. If the frame is flexible, it will flex when the strings are vibrating and it will rob energy from the string, making it sound softer, or "muddy". If the frame is rigid, it won't rob as much energy from the string and they will sound brighter/clearer. No need to get any further into detail than that. If you do, it's likely you're taking a wild guess, or trying to sound like the smartest guy in the room by debating things on a microscopic level that have no practical value.
If you attached bass strings to a steel I-beam with a pickup, it wouldn't sound like steel. It would sound like bass strings attached to a very rigid frame.
If you attached bass strings to a blank of willow with a pickup, it wouldn't sound like willow. It would sound like bass strings attached to a soft, flexible frame.
Maple doesn't have a sound. Ebony doesn't have a sound (Unless it's the thin top of an acoustic instrument and it literally is what is making the sound, but that is a compLETELy different set of circumstances than a solid bodied electric instrument). Rigidity is a property of the frame. The frame is something to mount the strings and electronics to. The strings vibrate. That vibration is transduced into an electrical signal. That's the sound. The strings vibrating in a magnetic field. I can build a bass out of poplar and build it in a way that it would be just as rigid as a bass made from maple. And all else being equal, you wouldn't hear a difference if you didn't already know which was which. Would you hear a difference between an acoustic with a poplar top and one with a maple top? Most definitely.
There's plenty of anecdote, plenty of theories, plenty of imagining how it all works and plenty of hairs to split amongst the theoretical physicists, but I like to bypass all that and look at it in the simplest terms. Because that's all that's actually useful.
Knowing how pickups work, what to look for in a piece of lumber and how to navigate construction methods to achieve a good frame is all you need to build a good electric instrument.
Once you know how to build a good frame and put that aside, 90% of your sound is your pickup design/placement, controls in the signal chain and the rest is what strings you have, their condition and your playing.
Not going any further than that helps me avoid analysis paralysis and also from getting ripped off if I were in the market as a buyer.
If you think I'm full of it and think there's a relationship between the type of wood your bass is made of and the pickups, or that the pickups are sensing vibrations through the wood,......string your bass up with nylon strings and let me know how it sounds at the speaker.
If,.....and that's a big IF, you hear a difference between a maple FB and an ebony FB on 2 otherwise identical fretted basses,...it's because one board made the neck stiffer than the other. It has nothing to do with vibrations traveling through the wood, being colored by it and then getting soaked in through the pickups, through the wood.
That's why the guy in that vid that keeps getting posted, was able to get 2 different guitars to eventually sound identical and then attached the strings to 2 work benches and it still sounded exactly like the same guitar.