The difference between as such and therefore
TLDR: As such means ‘in the exact sense’, while therefore means ‘as a consequence of’.
Pomposity is partly to blame for this occasional mix-up because using as such in place of the good old therefore apparently gives the impression of sophistication. Well, to cut a long story short, using these two terms interchangeably can often bite a writer on the gluteus maximus.
as such (phrase)—in the exact sense; in that exact capacity
Well, we weren’t invited as such.
Sammy was the captain of the team and, as such, got to pick her lineup.
Josephine came first in the class and, as such, got special privileges.
therefore (adverb)—in consequence of that, consequently; as a result
The shop was short-staffed, therefore, the customers were forced to wait.
I was concussed and, therefore, had to eat plain food for a week.
As you can see, when using therefore, something occurs as a direct result of another thing having happened first. Because I was concussed, I had to eat plain food for a week. Because the shop was short-staffed, the customers were forced to wait.
However, in the examples for as such, the subjects are entitled to something. Due to the fact that Sammy was the captain of the team, she was entitled to pick her own lineup. Since Josephine came first in the class, she was entitled to special privileges.
This can get a little confusing in some contexts and, yes, as such and therefore can sometimes be interchangeable. However, as a writer, be mindful of exactly what you mean to say and pause for a moment to consider which term to use.