You didn’t look too hard then. Deja vu got released recently. It’s a chain from unprivileged to bootrom. Got fixed in 8.0.0, the very latest firmwares. Look it up at https://switchbrew.org/wiki/Switch_System_Flaws
It’s currently the only known chain, and might be the only one in existence. And yet it’s a big threat. In practice, A Dark Room isn’t a particularly interesting entrypoint due to requiring an usb keyboard (web browser is easier to open). But it's understandable that Nintendo would want to keep those entrypoint to an absolute minimum. Especially since newer hardware revision exist which fixed Fusee-Gelee, the BootROM bug you talked about.
It’s currently the only known chain, and might be the only one in existence. And yet it’s a big threat. In practice, A Dark Room isn’t a particularly interesting entrypoint due to requiring an usb keyboard (web browser is easier to open). But it's understandable that Nintendo would want to keep those entrypoint to an absolute minimum. Especially since newer hardware revision exist which fixed Fusee-Gelee, the BootROM bug you talked about.