I feel so torn on this project. On the one hand, I want to root for sebmarkbage, who has done so much for the field.
On the other, as someone who used to do some "JS platform" work at a tech company, I really don't want Rome to catch on. Yet Another Standard is really painful for the ecosystem, and while it's obnoxious that you need so many tools, at least we've finally settled (mostly) on good answers for each vertical. TS, ESlint, Prettier, Webpack, Babel.
Now, would it be nice if there were an underlying engine/server that all tools could use to share an AST without reparsing everything? Sure, I guess. Would it also be nice to have one tool that wraps the others, at least when you're getting started? Yes, though I think create-react-app has blazed that trail pretty well.
The thing is, all those tiny little details from Prettier and ESLint and Webpack really matter – Rome will take years to achieve the number of lints that ESLint has, and even more years for the community to agree on which ones matter. Similarly, every corner-case of prettifying will have to be considered anew, and every edge case of bundling rebuilt or reimagined.
I love to see a talented person take on something insanely ambitious, so I wish him luck and hope he proves me wrong. But if Rome succeeds, it'll be a big pain for a lot of people as they try to port everything over, and for the community as they grapple with dueling standards for how things should be done.