Looking over environment aspects of production below, all the recent studies disprove what was assumed so far and your comment.
https://en.wikipedia.org/wiki/Environmental_aspects_of_the_e...
One such: "A 2020 study from Eindhoven University of Technology mentioned that the manufacturing emissions of batteries of new electric cars are much smaller than what was assumed in the IVL study (around 75 kg CO2/kwh) and that the lifespan of lithium batteries is also much longer than previously thought (at least 12 years with a mileage of 15000 km annually). As such, they are more ecological than gasoline-powered internal combustion cars.[58] [59] "
This doesn't even take in account recycling.
As for harmful chemicals during mining and manufacturing - it's the same for any other mining operation like gold and so on, states put in place laws that you cannot use harmful chemicals and other solutions are found. (cyanide in gold mining comes to mind)
This only works if you actually have an alternative. What if your process requires benzene and there are no alternatives?
It depends on how you define better, though. For a city, yes, there is no air pollution coming directly from an electric car, but it's significantly more polluting in the manufacturing process compared to an ICE car due to the special materials needed. An example is lithium, which uses solvents and chemicals that are toxic during the mining and manufacturing process, which then produces extremely bad waste that's hard to deal with (and often isn't, causing significant problems for the local area). This is a particularly bad problem for electric cars since they need very large batteries. This process (and others) need to be improved significantly and recycling programs need to become a better alternative to simply creating the materials from scratch to really say that electric cars are unequivocally better than ICE.