Do you think a gun is necessary for self defense?

For the average person who isn’t particularly athletic or trained in any combat sports, do you think they need a gun to defend themselves? Especially considering that there are trained killers like MMA fighters among us. Although it is unlikely for an MMA fighter to pick a fight with an average guy, people can do all sorts of crazy things when they’re drunk. You just never know. Of course if the average person does own a gun then they must have proper training on how to use it safely and effectively.