Google Native Client, or NaCl, is not as dead as has been previously believed. Although support for NaCl in websites and 3rd-party browser extensions has been removed, it lives on in some form. This bug tracking issue details the development in 2020-2021 of a C++17-capable NaCl compiler toolchain, codenamed "Saigo". CI-related commits show that it is actively tested on numerous platforms, so it is not just a ChromeOS thing.

After poking around a bit in Chromium Code Search, I still haven't been able to determine what NaCl is being used for. Chromium has a lot of "sandboxed" processes, but in general these are not NaCl-based. But as of now the code is being shipped with Google Chrome: inspection of a Windows install shows a nacl_irt_x86_64.nexe and various NaCl-related strings in chrome.dll. So the chances of it being available for any platform Daemon would want to support seem good. (Contrast this with standalone WebAssembly engines which are more popular for Linux servers and have not been ported to 32-bit architectures.)