Let's not define "environmental impact" solely in terms of carbon emissions and then do a trivial comparison to some mundane activity.
Smartphones may have a low carbon emission footprint relative to some other things (numbers I found varied widely) and that still wouldn't be a good argument for discarding them unnecessarily.
Their production and disposal has a great deal of other side effects that aren't defined by carbon emissions, including the mining and refining of rare metals. I would very much like to link a comprehensive examination of this here but I regret that I haven't got one in my bookmarks already and search results are being as useless as usual. If anyone else has a particularly great link to share I'd love to see it too.
You're definitely helping me prove my point, what are those other environmental impacts?
Let's imagine we can stop a single car from needing to be produced: that will dwarf all the mining impacts from probably thousands of phones! Cars are soooo much worse along any angle you can possibly imagine, yet people are misdirected from their use of cars to worrying about miniscuke rounding errors from their phones.
Suppose (made up scenario) we can stop a million phones being discarded every week by mandating that camera modules have to be replaceable by third-parties.
We can drop that legislation tomorrow, basically no problem.
Are you gonna say, no we have to wait and do cars first because a car is equal in carbon to 20 phones (or whatever).
Cars are one of the large container targets, but it takes years to change urban environments, to build transportation infrastructure, to change building zones, etc., to prepare the way for people using alternative transport (or none). Unless you can win over your citizens (and politicians who are in lobbies pockets) for a grand plan like 'no more new cars from now on'.
That cars are such a slow mover is the reason that we need to focus on it now, rather than later.
I don't think you hypothetical would change even a tiny fraction of phone replacements, but even if it did, legislative bandwidth in the US is extremely low and should be reserved for the high impact changes. Anything that distracts from the must-do messages is quite likely to be harmful.
We make people jump through all sorts of hoops for plastic straws and plastic bags that have approximately zero environmental win compared to far smaller changes to their car use.
The real problem is the social attitude that cars can not be touched or criticized. That needs to start changing.
Our phones are not the core of climate change, our cars and all the massive environmental damage from mining the necessary minerals for them really are.
The first step when doing optimization is to measure, so that one knows where efforts have significant results.
I am arguing that our efforts should be in proportion to their payoff for environmental efforts as well.
Or more precisely, we should spend our environmental efforts in ways that maximize their returns.
Thus, here I am spending lots of time commenting on how a tiny minor change in driving habits will have bigger effects than large changes in phone habits.
Urban planning in the US responds to the demands of the residents. We should be asking all residents demand alternatives to driving.
Urban planning in the US was a result of the oil lobby. It has nothing to do with the demands of residents except insofar as they were also brainwashed by the oil lobby.
It can't be limited to just the oil lobby, it was a general movement with lots of different proponents, not the least the car companies! In fact the car companies quite a bit more. But the urban planning establishment definitely adopted car-only infrastructure with gusto, without any direct oil or car money behind it.
Smartphones may have a low carbon emission footprint relative to some other things (numbers I found varied widely) and that still wouldn't be a good argument for discarding them unnecessarily.
Their production and disposal has a great deal of other side effects that aren't defined by carbon emissions, including the mining and refining of rare metals. I would very much like to link a comprehensive examination of this here but I regret that I haven't got one in my bookmarks already and search results are being as useless as usual. If anyone else has a particularly great link to share I'd love to see it too.