You make a very valid point. It can be easy to forget to consider environmental cost when we consider the cost of an item.

I hate smartphones with a passion, so just use an old dumbphone. I face a lot of pressure through work to have one though. I'm thinking that if I do eventually get forced back into smartphone ownership I'll opt for a Fairphone 2. Major benefits being the improved environmental consideration, the ability to run Lineage OS (so no Google), and the modular approach makes it easy to hack/repair. Main downside is that it is very expensive (to me anyway... I get that many people these days seem to think £1,000 is a reasonable sum for a Facebook/Instagram PDA!).

Other phones of the same caliber have the same horrors, you just pay an higher profit margin.