[bri3d]

Yes, a full replacement absolutely makes sense in this situation! I don't think there are many Windows infotainment units left these days. Analyzing the binaries to figure out the meaning of the CAN traffic is an awesome (and underutilized IMO) technique - I see people sit and stare at CAN dumps in a vacuum a lot when really, whatever checksum or data they're looking for is often right there in the code.

[fmntf]

Actually there still are a lot of Windows ECUs in the wild. I analyzed the update packets of newer cars than mine (equipped with Uconnect) finding even sndrec.exe and the default page of IIS! Fortunately my company produces Linux-based ECUs, and we use Windows only for Autosar stuff.