1) Tesla is making vehicles with EV drivetrains at cost parity or less than an ICE car (depends on the actual reporting on Tesla's per-car margin accuracy). This number is somewhere around $100/kwhr at the pack level.
2) EV drivetrain cost has been steadily falling at nonlinear rates for a decade, with very much runway.
3) CATL and other battery suppliers have released 150 wh/kg sodium ion and 200+ wh/kg LFP in mass production. The sodium ion density (150 wh/kg) is somewhere around a 300 mile range car with good engineering. The LFP density (200+ wh/kg) should be good for a 400 mile car.
4) the pack-level cost of the cells remains to be seen, but likely the sodium ion pack level cost will drop to 50$/kwhr give or take. The LFP will be in 60-80/kwhr. Note that this is not dependent on lab-to-factory maturation. The cells are already beginning mass production, and the full cost drop is just a function of boring traditional factory construction and logistics.
This means that in about 2-3 years, a car company with a decent EV engineering team will be making cars that cost them, at the core "guts" of the vehicle, about 1/3 to 1/2 less than an ICE car.
If you've driven in a Tesla, you know an EV produces a lot of torque, is quiet, smooth, and a very good riding experience. The downsides of slow recharge are steadily improving.
But if an EV costs 25-40% less than an ICE, and your car company cannot make those vehicles, your car company will cease to exist in short order.
The last five years where VW and other companies started doing the large EV investments, they were following long term trend lines, without acutal substantive technological pathways. So conservative companies like Toyota / FCA / etc could plausibly drag their feet and sell wait an see.
They cannot do that anymore, which is likely why Toyota is making all these announcements only 1 year after questioning EVs and pushing Hydrogen for the nth time. It's the new Sodium Ion and LFP going into production, which is a tangible no-projecction add-up-bill-of-materials that equals: the ICE is not a competitive economic product in the very near future. It is obsolete. Yes it will have inertia, but its days are numbered.
Of course, those numbers are just for the sodium ion / LFP stuff that CATL is putting into production this year.
The roadmaps for sodium ion in 1-3 years is to hit 200 wh/kg (the 400 mile car, or a smaller/cheaper pack for a 300 mile car), and LFP to hit 225-250 wh/kg (the 500 mile car, a cheaper pack for a 400 mile car).
So go ahead and take all my calculations for 150 wh/kg sodium ion and 200 wh/kg LFP and slash them by another 20-30% for reduced drivetrain costs.
Now, what's in the wings in the 5-10 year range? solid state batteries, sodium-sulfur or lithium-sulfur batteries, all in various stages of lab-to-commercialization. Energy densities in the 300-500 wh/kg. Yeah, drop those drivetrain costs even more.