Yes but I only need to have 0.00000000002% of the star systems in the galaxy to be habitable for you to be wrong. This doesn't account for the possiblity of multiple planets in the same star system.
0.00000000002% is 2 parts in 10^13. But there are only 4 x 10^11 stars in the Milky Way. And spectral type G stars make up only 14.6% of the total, or about 58 million stars. But most of these are too young, too active, too close to the galactic core, or too metal-poor to have planets. So you have already whittled down the 10^11 stars in the Milky Way to perhaps a million.
I am saying (well, I learned it from Ward and Brownlee) that Earth is one in a million.