Colloquialisms like "in real life" are correct usage. Just because it's not literal doesn't mean it's wrong because the information contained in verbal and written communication is affected by its context, including the society and culture it arose within.
And who is the arbiter of which use is correct? Language is always evolving and changing, the definitions of words you grew up with were just the definitions at that time. The meaning of a word is only defined by how people use and understand it.
It is possible to use words incorrectly, but if 90% of people use a word in a certain way, that becomes the definition.
I think the simpler way to think about this is that it's definitely possible (and common) to use words confusingly.
That is, you can use words in such a way that many people misunderstand what you mean. You could then call that usage "incorrect" if you want, and I wouldn't quibble too much with that, but the more important reason not to use those words in that way is that people don't understand you.
But in this case, this usage of "in real life" is not confusing anyone. Even those who pedantically quibble with it being "wrong" actually understood what was meant.
People can mean something else than you when using the same words, and they might not be wrong as those word definitions might be acceptable too (and they might change over time too).