Let's make a distinction here. A symphony is a composition in a specific type of musical form written for an orchestra, which is a type of musical ensemble.
To state it simply, a symphony is a very specific type of long song, whereas an orchestra is a type of band.
There are many kinds of musical pieces written to be played by orchestras that are not symphonies. These include concertos, sonatas, suites, oratorios, and cantatas.
These days the term symphony is used incorrectly to describe an orchestra. People say "I'm going to see the Atlanta Symphony" when what they mean is "I'm going to see the Atlanta Symphony Orchestra". The Atlanta Symphony Orchestra is an orchestra that plays symphonies, as opposed to an orchestra that plays ballets or an orchestra that plays operas or an orchestra that plays oratorios or cantatas.
Calling an orchestra a "symphony" is a modern mistake, something that's appeared in the last thirty years or so.
Here's my point: Yes, Beethoven's Ninth is, basically, the first symphony to feature a chorus.
There are many pieces going back centuries before Beethoven that feature an orchestra and a chorus, but those musical works are not symphonies. They are oratorios, or operas, or ballets, or other forms. Bach's B-minor Mass features a chorus and an orchestra, but Bach's B-minor Mass is not a symphony, it is a Mass. Handel's Messiah features a chorus and an orchestra, but Handel's Messiah is not a symphony, it is an oratorio. Beethoven's Choral Fantasy is not a symphony.
And by way of establishing my credentials, I'm the volunteer business administrator for the Atlanta Baroque Orchestra, which has been performing for fifteen years. They are an orchestra, but they only rarely play symphonies. They more often play concertos, suites, cantatas, and other forms.