How long does it take to get good at acoustic guitar?

Okay I know people are gonna say depends, on talent, time, etc. Let
me try and fill in the details of what I have done so far. I have
been playing for about six months with lessons. I can play most major
and minor chords at a decent rythm and pace. I practice a lot about 3
hours doing scales and chords and songs. Then I take a break and
later the same day play for about 2 hours just playing by ear writing
stuff etc. I met this guy the other and his brother and him both have
been playing about 8 or 10 years and they were pretty good. They
didn't believe that I had only playing about 6 months they thought
after hearing me play that I had playing about at least 5 or 6 years
minimum. I have got this a lot many people thinking I have been
playing at least 5 years or more. Now, maybe it's because I play so
much each day not sure. So if anyone has been playing acoustic guitar
under ten years what is your thoughts. Right now I am working on a
Dave Matthews song called So Much To Say and sounds pretty good
according to my teacher, also I play a Martin acoustic with heavy
strings. My friend who plays acoustic also said she could barely hold
down a bar chord because of the strings she uses lighter strings.