The author specifically and explicitly pointed out 3 times in 2 paragraph that these were new to them, not to the world at large. In fact, they spelled this out very explicitely in the paragraph following the one you selectively quoted:

> Many of the new concepts weren't novel to Rust. But considering I've had exposure to many popular programming languages, the fact many were new to me means these aren't common features in mainstream languages.

And… they're right. Other languages cropped up with overlap around the same time (mostly Swift), but sum types, pattern matching, option types, … were not common features, and borrow checking remains rather unique.

I think you might be misinterpreting that as "Rust introduced these things" rather than "I learned about these things from Rust".

The author does mention a Haskell/Scala like language missing from their list of languages they have written, but then they do include Erlang which I believe has pattern matching as a fairly core construct? This does lead me to doubt how much Erlang they've written, and in turn how much they've written across all of the languages mentioned.

He means Rust introduced these concepts to him, not in general.

When rephrased as "Rust introduced to me a number of new concepts, like match for control flow, enums as algebraic types," it's much more clear what he means. We all learn somehow.