If your question is "why isn't Toyota just catching up since the differences are so minor in my mind?" maybe ask them, but we haven't seen it happen yet. I've driven Toyotas and liked it, I'd welcome more Toyota full EVs, but they seem to be struggling with full EVs so maybe it's not that minor in practice. That's the main thing that I can tell you.
I'm sure you can google on the topic, takes that are sympathetic https://insideevs.com/news/650150/toyota-says-ev-extremists-... mixed https://slate.com/business/2023/01/toyota-electric-vehicles-... and negative https://thedriven.io/2023/01/30/toyota-faces-disaster-unless...
I'll add a couple of things that I do know: car companies that have been in business for decades and operate at huge scale in big factory assumbly lines across global supply chains are, as I said above, "lumbering beasts", the new models are planned multiple years in advance. They don't turn on a dime, changes in Toyota management this year translate to new models on sale in 2026 or thereabouts. VW, BMV etc have a head start, as they have EV models out right now, and not the 1st generation of them either - e.g. I see VW ID3s locally, and the VW ID6 will be out by end 2023. Toyota's 2026 model will compete with an ID6 successor. And a Polestar 4 successor, etc. This is hard, from a standing start.
You mentioned the Prius. Toyota owns this market, sure. I see lots of them around, it's the vehicle of choice for "minicab" private hire taxis. But for Toyota, that's also an barrier to doing anything that takes sales away from that market.
If it was so easy to pivot to full EVs, would people be saying "Toyota faces disaster unless new CEO performs miracle" ?