[E. Pluribus Unum]

I noticed a trend on the internet in last few years as is shown in the text in post #5 of putting the dollar sign after the amount like this: 17$ instead of the correct $17. How did this start?

Same reason they incorrectly punctuate end-of-sentence apostrophes as...

"xxxxx".

instead of doing it correctly as...

"xxxxx."

Obviously, they were not taught proper grammar and punctuation by Dominican nuns. 🤡

[powerset]

The rule that says that
    "xxxxx".
is wrong while
    "xxxxx."
is correct, is a grammatical rule up with which I will not put.

Since it's only the "xxxxx" being quoted, including the period quite contradicts the syntactic structure of the sentence (not to mention essentially all programming language syntax).