I would agree, at least I am like that when using Rust (though I don't contribute).
And it's true that this is a shortcut to burnout.
> or that its six-week release cycle attracts people who think that a year is a long time
I don't speak for the Rust project but to me this always sounded like a measure to avoid stagnation. Having six week slices helps remind people that this is not only a labor of love; many people out there are counting on you to get your stuff right.
Obviously Rust isn't governed like a commercial project (and thank the gods for that) and obviously many things still take years to complete but for me at least the six weeks release cycle would serve as a periodical poking a la "Hey, is your stuff progressing even a little?".
Don't know though, could be just my interpretation.
Linux shows us at least one way to run a successful long term project. What is their governance model?