Depends on the guitar too. Nylon string guitar takes a significantly more precise technique to get a good reliable sound out of up and down the fretboard. Some styles of steel string acoustic sound crap unless you play them the right way. But a bog standard electric guitar is going to sound 'like a guitar' pretty much automatically. Of course, that also presents a slight issue as well I think. Because it is generally easy to get a workable sound from an electric guitar straight up, players tend to spend a lot of effort into developing their signal chain to create their ideal tone overall. Electric guitar is not generally an instrument that sounds great 'going direct' in a musical context where a lot of the sound is going to come from your amp, speaker and whatever boxes you put in front of it.

Guitar is also disadvantaged against several other instruments in terms of learning to read standard notation. If you see a C you know it's either 3rd fret A or 7th fret E but it's also a question of which finger to use on each fret, so that can be 10 options for how to play a specific note and which one is correct depends entirely on the context overall. Which is not to mention chords. As anyone who can read proficiently knows, in a performance setting there's no tolerance for 'half a second' decision making but the nature of a guitar makes it take slightly longer to get those facilities on auto-pilot compared to say, a saxophone where the note-finger-page relationship is a lot more direct and intuitive.

But yes, overall, Guitar is relatively easy to pick up especially in the context of how it is played in most modern settings and it's no coincidence that once we started making 'guitar music' in pop culture that the floodgates opened either.