You can create dictionaries on the fly. But dataclass objects require defining that dataclass first. The type safety (and LSP support) story for accessing individual dataclass fields is better than for accessing dict items (sometimes even when they are TypedDicts), but for iterating over all fields it's worse. dataclasses are nominal types and can contain additional logic, TypedDicts are structural ones, overall simpler, can be more convenient and lead to looser coupling. Dataclasses use metaclass and decorator magic while TypedDics are just plain dicts. Etc.

Let me make this more concrete: Those sysadmins frequently need to process and pass around complex (as in heavily nested) structured data. The data often comes in the form of singleton objects, i.e. they are built in single place, then used in another place and then thrown away (or merged into some other structure). In other words, any class hierarchy you build represents boilerplate code you'll only ever use once and which will be annoying to maintain as you refactor your code. Do you pick dataclasses or TypedDicts (or something else) for your map data structures?

In TypeScript you would just use `const data = <heavily nested object> as const` and be done with it.