For high Fidelity, you need to have a stiffer cone / dome and high magnetic flux density driver ( more than 1 tesla) / the properly engineered acoustic chamber.
I think this phone has enough stiff cone/dome but I am not sure it has high flux magnet / coil and motor structure combination.
Also stiffness to mass ration should be sufficient.
If they declare all those factors are declared on their site, then the sale would be easier.
For example of Audioquest headphones, they declare their motor / speaker / the acoustic chamber in details and they are so persuading and appealing.
Because all those items constitute the acoustic fidelity through voice coil motor and the speaker in the chamber.
Why do they not declare?
Maybe they have had difficulties for getting engineering tool and trained engineers to do so?
You do realize what demographic they are targeting with this product, right?