How Important is Pedantic Grammar?

NOTE: English majors may want to skip this post.

I was talking to someone, and they were like "Isn't the point of language to helpfully communicate ideas?"

Quick, how many mistakes are in that last sentence?

• Singular "They"
• Quotative "Like" (And I was like...)
• Splitting infinitives (to <adverb> <verb>)
• (I probably made some more mistakes too; grammar's not my strong point.)

A better question is "Was what I said clear?" I'd say, yes, it is clear. The sentence would have the same meaning without the "mistakes" (I was talking to someone, and he or she said "Isn't the point of language to communicate ideas helpfully?"), but is it worth the trouble? When are grammar rules important for defining the structure of a language and when are they meaningless pedantry?
For example, English lacks a gender-neutral singular pronoun. Rather than invent words to fill the gap, why not use what we already have? Embracing singular "they" just makes sense.
The same could be said for splitting infinitives. Should Star Trek's opening be changed to read "to go boldly where no man has gone before?" That would be ridiculous. "To boldly go" is just as clear, if not clearer.
There's less of a case to make for quotative like, other than the momentum behind it is much greater than those who want to stop its usage. It's simpler and easier to update the language to reflect those who use it rather than to attempt to force arbitrary rules on English speakers.
Honestly, this can all be summed up with a single question. What is the point of grammar? Is it to help organize coherent thoughts or provide strict rules for language? That's a question for you to decide.

See you next Wednesday at 15:30!