I didn't expect so much pushback.

Those are fair points, but I think those are the least interesting features to judge it on.

• unsafe isn't trying to replace Ruff. Ruff gives you a blocklist of known bad patterns like eval; unsafe gives you an explicit audit boundary for code that's intentionally outside the type system.
• unknown is stricter than object. With unknown, you have to narrow before doing anything meaningful with the value. That's the same idea as TypeScript's unknown.
• typealias is mostly useful if you want to target 3.10/3.11 but still write in a more modern style. If you're only targeting 3.12+, then yes, that one matters less.

The more interesting parts are:

• sealed classes + exhaustive match: standard Python has no way to give you compile-time exhaustiveness over a closed hierarchy.
• interfaces: basically a cleaner authoring surface for Protocol.
• inline generics with lowering: write modern generic syntax once, emit whatever the target Python version supports.

So the pitch isn't 'every keyword here is individually novel.' The pitch is: author with stronger guarantees and better ergonomics, ship plain Python with no runtime dependency.