You are right, but ARM is getting stronger. In IVI you mostly have no other choice (only Intel), since the main contenders (SH4, top-end PowerPC) are now discontinued. Which I personally thought was a good thing, because in IVI you want to reuse lots of existing software from outside of automotive, which often has only support for Intel and ARM.

For other domains other architectures .e.g from Renesas) are still going strong. 16bit is however nearly dead, since most standardized software (Autosar) requires 32bit. However I also see ARM cores getting traction there. But even if they are coming in it will take some time until you see them in real cars. Keep in mind that development cycles are >= 3 years, which means even if someone decides to use an ARM core in a ECU which is designed now you won't see it before 2020 on the streets.