What does “main” mean? Main processor for a flagship iPhone? Or main processor for a HomePod?

There’s a lot of “main” processors for Apple’s devices at this point.

I would be deeply skeptical of a brand new flagship iPhone <n> Pro having an Intel fab’d SoC until at least a few years into this arrangement.

Also an “exploratory discussion” is not the same as a signed contract. Apple has tons of custom silicon now. There are many low risk ASICs Apple could kick the tires with.