No, not a typo. I just think that at the time they were playtesting the game before it was released, there wasn't this huge swathe of players all bum-rushing Great Weapon Fighter / Sharpshooter / Polearm Master / Lucky along with maxing out primary stats... which completely skewed the view of what feats could / should / would be used for.If there any good reason why the Athlete Feat shouldn't include Proficiency in Athletics?
This seems like a no-brainer & a really weird omission. Typo?
And I don't think it's that shocking, as I suspect this is extremely difficult to figure out prior to a game's release into the wild. When you're in playtesting, your large set of playtester groups are asked to test a lot of different stuff, not just "make what you want as often as you want"... and thus they probably had no idea of the the shear number of players who went straight to the massive utility and power of the super-combat feats and completely tossed away all of these more fluffy, story-and-character-defining feats. Then they saw for the first years after release, conventional wisdom determined that ASIs and the super-feats were the only things worthwhile in the system, everything else was "under-powered". Had the designers felt which way this wind was going to blow, I wouldn't be surprised if they HAD added Athletics as a proficiency and/or double-prof bonus to the feat to give it more oomph.
But this is why we all are free to house-rule the game... our 20/20 hindsight tells us what our tables need to have to make things like feats important and we can edit, amend, or create anew the feats we are going to need to make our players happy.