Isn't that how it's used now? (Although I wouldn't say "sarcastically" but rather "metaphorically".) I would define it as referring to a task that is very difficult due to a lack of outside support.
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nowadays i hear it exclusively used to tell someone to 'toughen up'
I figured that the people saying it meant "you need to find the strength to do this yourself since no one is going to help you".
"You need to find the strength to do the impossible because we won't spend money on minorities and poor people" is how it is used today.
That’s what they mean, but they’re idiots using it incorrectly.
How is that an incorrect usage? The phrase is a metaphor that describes a task that's apparently impossible without outside help. They're using it to say "perform this task without outside help anyway" which can be callous but fits the metaphor.
No one can pull you up by your bootstraps. They can pull your boots up by your bootstraps. The original phrase refers to an impossible task whether or not anyone else is involved. That’s why it’s sarcasm.
Sure you're not thinking of "pull yourself together"?
While I don't appreciate the way this phrase is used currently, I'm not sure it is worthwhile getting too deep into it. Meanings change over time like discussed in the "hey" post the other day or more recently with the increased meanings for literally.
I guess nobody ever told the boomers...