Is your feature request related to a problem? Please describe.
I wouldn't call it a problem as much as a quality of life-issue. When using the various from-x commands, the hyphen takes more work to type than a space.

Describe the solution you'd like
I'd like to be able to use the various formats as subcommands of a general from command, so that I could drop the hyphen. E.g.:
open file | from csv --headerless , fetch url | from json, etc.

The various subcommands would take their regular args as per usual.

Describe alternatives you've considered
N/A.