Hate to sound preachy, but compare to Python developers, who very carefully maintain and update their stdlib. I feel like it is risky to commit to using Ruby for the long-term.
Is that a joke? How many different interfaces are there to popen(3)? How many different ways to get the current time? If Ruby's standard library is a ghetto, Python's is a jungle. If you like Python, I don't know why you'd even think about "committing to Ruby for the long term"; you're a Python dev. They're practically the same language. Stop trying to pick fights.
popen, popen2 - both deprecated. The new "proper" one is available since 2.4 (quite a long time now) - subprocess.
> How many different ways to get the current time?
time.time() Is this that bad? Sure, popen and popen2 are silly, but they're left for compatibility, while subprocess was introduced to update stdlib (as OP claimed). It's hardly a jungle...