react-icomoon has a quirky CommonJS export with a hack meant to make it work when imported from an ES Modules context. The idea was that would set exports.__esModule to enable the hack, and you would export a prop named default that would be the "default" import for the ESM.
This hack was supported in Webpack 4, but not in Webpack 5. There's a lot of noise about this on GitHub, but the Webpack team points to Node as no longer supported this hack either as justification for pulling it out.
The react-icomoon package uses this hack. I tried upgrading it, but the latest version still had the same problem. To get around it, I just update the code to access .default directly.
Note that this means lib/components/SWMansionIcon.react.js wouldn't work in a React Native context, despite react-icomoon claiming to support React Native. But we don't need it on React Native since we use createIconSetFromIcoMoon from @expo/vector-icons instead.
Depends on D6703