What are some places that don't look like Linux but actually are?
Amazon Lambda, Azure Automation, GitHub Actions, Amazon CodeDeploy, Azure DevOps, anything Android (not GNU, but runs a Linux kernel), SteamDeck, almost every miniature gamesystem (Genesis Mini, PlayStation Classic, etc), and a variety of the smallest chips that usually run raw C code are gradually getting powerful enough to have a Linxu kernel (I E. Raspberry Pi Zero replacing Arduino in various recipes).
With the SteamDeck's recent rise here's also been a shift towards video games being written first for Linux, then cross-compiled for Windows and much later ported to Nintendo Switch.
I don't know if we have confirmation on whether PlayStation and XBox or Switch run Linux under the hood yet.
Switch almost certainly doesn't (or at least not a recognizable version) or we wouldn't see the release delays we currently see.
It seems like the vast majority of portable hardware above very low power stuff runs a Linux kernel now, even when the rest of the OS is unrecognizable. Mostly via Android, but in exceptional cases with a custom OS.