I actually find the shorter keywords aid readability. Code, just like prose, has a maximum line length after which readability starts decline. Given that we only have so much horizontal space to work with, shorter keywords allow one to use more descriptive variable and function names. Given that the number of keywords is fixed and the number of variables and functions is unlimited, I'd rather be terse in the former and verbose in the latter.

Also, Rust does care a great deal about readability. You might scoff at this statement, but it's true: Rust's syntax works hard to strike a balance between all of clarity, consistency, regularity, readability, and familiarity. As the language gains wider use, understanding of these constraints improves; modern Rust has removed 95% of the sigils that characterized ancient Rust. There used to be tons of sigils, and many were largely inscrutable: ~, @, +, ++, -, more that I've forgotten. Now there's only two: & (for references, a sigil taken directly from C++) and * (for unsafe pointers, a sigil taken directly from C). And there are even some people who would like to see the * sigil for unsafe pointers go away.