For all the ones that mentioned about SSB being rated T....
Back when the first SSB (or Melee, but I'm not for sure) came out, the E10+ rating didn't even exist!! It was either E or T, and Nintendo had to go with the closest to it possible. Because it was a fighting game, they chose T.
The reason Brawl is rated T is because I guess Nintendo didn't choose to change the rating just yet, but the 3DS one is apparently E10+
So, yea....(LoZ:OoT and LoZ:MM probably have a similar reasoning, assuming they came out around that timespan as well)
I think the rating system is okay. Some people ignore it, but there are some other people who pay attention to it. When it comes to my mom and I, we briefly look at the ratings, but most things T or under she'll let me have.