do they have a roadmap for charging infrastructure? What if they sell millions and it takes 20min to charge knowing that most people will charge at similar times when going to work?

This assumption is wrong that everyone needs to charge before going to work. Once people started hitting queues at charging stations they will start charging at home over night. Though personally I think work place charging stations should be promoted where electric cars get charged at work using solar energy instead of at night at home using fossil fuel based electricity.

This test in LA is interesting, using existing power infrastructure:

https://electrek.co/2019/11/13/la-adds-hundreds-of-ev-charge...

Wouldn't most people just charge at home, overnight?

That may work in suburban America but I'm not so sure about the rest of the world. Most of my life I've lived in apartment complexes (US) / blocks of flats (Europe) where there was no car charging possibility when parking. It would require huge infrastructure changes to allow most people to be able to charge at home and work, this is different from gas powered vehicles where you need a relatively small number of (centralized) points that distribute fuel. With electric cars that number needs to be much larger and it's distributed.

It can be done over decades for sure but it won't happen overnight.

I can see charging trucks going around all night and topping vehicles up mobile resupply like.

charging trucks that run diesel generators ?

Or with big batteries.