Imo the big problem is that 'affordable mass-market EV' is just a contradiction - once you build a mass-market EV most people would willingly buy - one with >400km range with decent enough fast charging for road trips, you've very close in terms of hardware budget to something that's decidedly upmarket, like a Model 3 - just add a bigger chassis, some tech gadgets and a more powerful motor, all of which cost little compared to the battery and inverter.
For an ICE car, this issue doesn't exist - you can put in a 900cc 80hp engine into a tiny car with basic trim and the end result would still be a car that can take you everywhere.