Well, it's better to look at the odds of every method of finding a shiny to see which game is better.
- the Masuda Method raises the probably to about 1/1365
- the PokeRadar method needs about 40-50 consecutive encounters of the same Pokemon until you have a good chance of finding a shiny; however it doesn't exceed the Masuda Method until about a chain-link of 33.
- Consecutive fishing is about the easiest way of getting a shiny Pokemon, and can help you encounter a shiny Pokemon from as small as a chain of 15 to maybe as high as 120. It's probability is similar to the PokeRadar, but some Pokemon can be found much easier than others (such as Luvdisc over a Horsea)
- Horde Farming with a Pokemon with Sweet Scent can raise your probabilities to 5/8192. Or you can use a good but very long and irritating method; you can kill most (not all) of the Pokemon in a horde and keep waiting for it to call to help and hope it's a shiny.
- the Friend Safari probability is unknown, but most cases I've heard is about 1/2500 or 1/2000
All of these methods are able in Pokemon X/Y, however all but PokeRadar are in found in Pokemon Sun/Moon (there is PokePelago instead of Friend Safari for Sun/Moon). So from this, you may conclude that Pokemon X/Y is better for shiny hunting since there is more opportunities, but both games work just as well.
*If you do however get the shiny charm, it can increase your chances about 300% higher than the standard.
Hope I helped! :)