Oh man.
The Olympic games are about elite level sports. Nobody cares if you or any of your friends are shooting air rifles. Air rifles are an Olympic shooting event. And who does fencing, or dives into the pool from a tower? Pretty much nobody.
Let’s check our egos. It really isn’t all about the age groupers.
The people selling air rifles care 
We could invent all manner of elite sport with contrived rules and movements. You need people to feed into that sport at the base of the pyramid. Ideally, at least.
It makes for a fun movie, but if every sport was essentially the Jamaican bobsled team, it’s not very sustainable.
Be that as it may, they’re not putting 14-year-olds on TT bikes and telling them to bike 80 km in a race, or run 18k competitively.
The base of the pyramid is not a bunch of men in mid life crisis with excess money to spend.
Oh man yourself! haha.
I agree that its about elite level, but the olympics is full of sports where “normal people” participate and contribute to that sport’s identity. ping pong. basketball. karate. weightlifting. volleyball. Sure, there are sports/events where they are uniquely “olympic”, but this isn’t how they all are. to say triathlon in the olympics should mimic the way the sport is normally done by regular people is not a hot take at all.
of course non of those athletes you mention earns any money.
so its always a mix of elite sport making it actually a sport the public can and wants to do.