The problem is AMP is very hard to program and debug. In embedded, one core is a scheduler and another is doing some real-time task (like arm BIG.little). In larger automotive heterogeneous compute platform, typically they are all treated as accelerators, or with bespoke Tier-1 integration (or like NVIDIA Xavier). And on top of that, OEMs always want to "reclaim" those spare cycles when the other AMP cores are underutilized, which is nigh impossible to do, so they fall back to symmetric MP. I think embedded is the only place for this to work right now.
EDIT: I'm not an expert in this field but I have been asked to do work in this domain, and this narrow sampling is what I encountered, but I'd like to learn more about tooling and strategies for more generic AMP deployments.