Other niche features like water resistance can be achieved other ways, like suitable cases or removable sealing compounds along seams. Engineers are clever, they solve problems the simplest way possible within a given set of constraints. Changing those constraints won't change the possibility of achieving similar outcomes.

> If more people wanted them, more people would sell them, but most people prefer the additional battery life, increased water resistance, and thinness of modern phones.

You're overstating the preferences and availability of alternatives here. All the best engineering talent went towards sexiness hype cycles, little went into making phones with that were more eco friendly.

Lots of people also liked Tho-Radia, a radioactive cosmetic from almost 100 years ago. That's not a justification for permitting it.