Actually neither. The best car is the one that you can actually buy. That requires manufacturing, logistics and supplies. The likes of Toyota have barely begun the process of getting organized there. Even if they had an amazing EV product (which so far they don't), they'd struggle to sell a lot of them because they simply don't have factories, battery supplies, etc. in place that they would need for that. And at the scale they operate anything that doesn't sell in the millions of units is not worth doing. Getting from zero to there will take them quite a bit of time and money.
Which is why the winners in this market so far are Chinese and Korean manufacturers. And Tesla. Unlike other manufacturers they have manufacturing dialed in and a robust supply line with batteries and other things they need. Their main challenges are keeping up with demand and keeping cost low while growing manufacturing capacity.
The pace at which this market is growing means that it is getting harder for the likes of Toyota to break into this market. The few EVs they have on the market are actually not made by them and also a bit underwhelming. For example the bZ4X is actually a BYD car with a Toyota logo. That might be their future: leave the manufacturing to specialized companies and simply milk the brand. They seem to still insist they'll have their own drive trains and supposedly amazing batteries. But so far there's little sign of them building factories for those. Maybe that will work for them.
The winner will not be the first one to the market, but the one at the right time with the best car on the market.