Athletes have been treated as bona fide celebrities for decades with marquee players achieving a similar level of fame as music and acting luminaries. Yet relatively few athletes hit this celebrity stratosphere and, in general, athletes tend to struggle more than other celebrities and influencers to build their own personal brands.Noncelebrity influencers on Instagram, YouTube and other social media gain significant followings, but lesser-known athletes seem to have a harder time building social media followings, which has …