Vaguely similar ideas existed in True Names and Neuromancer, but no, the metaverse as we imagine it today did not exist before Snow Crash.
Tons of visualization through art, and ways and means defined through story.
Of course tend to need to be very literal about these things.
Frankly a computer meta verse isn’t that interesting
I’d rather figure out how to grow neuron structures that let me believe or have skills in anything and just babysit this stupid fleshy husk literally