Are Hardwood Speakers Really Bad?
There is a way to make hardwood speakers that might be tractable, but the front and back baffles have to be made of MDF or ply. Correct grain orientation of the sold wood panels eliminates contrary seasonal wood movement.
As this maker in the video above shows cabinet resonance can be obviated with damping materials. Also, a great many DIY'ers use wood braces. Granted, these are relatively small in cross-section, so wood movement is not much of an issue. I only mention it because sold wood has it's uses in cabinet construction - it's not automatically some bug-a bear.
Also, solid wood cabinets are easier to finish than veneered cabinets which can be finicky because of the thinner and thinner veneers being used. If the factory finish is something like poly then the strippers needed can soak through the veneer and loosen the underlying glue. If these refinishing process is not the first rodeo and previous refinishing involved sanding the veneer, then you can get perilously close to sanding through the veneer which is a mini-disaster from a decorative standpoint.
Anyone wanting to build a solid wood or mostly solid wood cabinet would also be advised to use a high quality shellac and keep water away from speaker. Most definitely keep alcoholic beverages away from it too, but the advantage of shellac is that it looks great done right and can be easily stripped with alcohol.
Also, if possible use vertical grain wood if at all possible - it moves less and stays flatter. Ultimate wood would be vertical grade old growth macrophylla mahogany. Not cheap and not easy to find. Quartersawn Sitka Spruce might be really good but also expensive.
Somewhere on Youtube there is a video of a European maker whose solid wood speaker cabinets use resonance and tailored crossovers to good effect. I think he was Polish - can't find him though.