play the guitar vs play guitar

Question

I was taught that when we want to say "produce sound on a musical instrument", we should always use the definite article before the instrument ("play the guitar/piano/violin").

I did research on this, and I got the expected results from the dictionaries I use:

Jean plays the guitar and her brother is on percussion. ^{Cambridge Dictionary - guitar}

He learned to play the clarinet at the age of ten. ^{Cambridge Dictionary - play}

He taught himself to play the violin. ^{Oxford Dictionary - play}

(particularly, they all pertain to the skill these people possess)

Then I came across this thread. There, some people said "play guitar" is more common in the USA while "play the guitar" is BrE.

One trustworthy American English dictionary provided the next examples:

Howard Roberts played guitar and Schuur sang and played a Fender Rhodes piano. ^{vocabulary.com - guitar}

I never thought about combining it with drag, ’cause to me, well, drag queens don’t play guitar. ^{vocabulary.com - guitar}

Moreover, I generated the ngram graph and noticed that the expressions using the are way more popular than those without the article:

Now I am confused about which one is correct and whether they are both acceptable.

Answer 1

There are a number of ways to refer to a thing not as a particular instance but as the prototypical entity, as the class to which individual things of its type belong. Among them are the zero article and the definite article.

Did you look in the dictionary?

That idiomatic use is not referring to a particular dictionary (M-W, Cambridge, Longman's, Oxford, whatever) but to the resource in the abstract, the prototypical notion of it, the book that everyone knows.

There are sometimes dialect preferences for the one or the other:

They took him to hospital. ^BrE

They took him to the hospital. ^AmE

These are therefore equally viable expressions of the fact that you can play that kind of musical instrument:

I play the guitar.

I play guitar.

Another use of the prototypical meaning is when a musical group, a band, typically includes a guitar. In this meaning the sense borders on that of a role.

He played guitar for that band at Woodstock.

He plays washboard for the Slow Pokes.

And then we have the related phrases that ultimately derive from this idea of a typical role:

They sang backup.

He rode shotgun.

He flies copilot for Qantas.