I'll bet that 90k-100k for an average Ironman completer/competitor is probably close to the mark (combined income).

The entry fee alone is $500+, and most folks get hotel on top. Plus you have to fly the bike out. You're looking at a $2-3K outlay just for the right to show up and race one single race.

Most competitors do more than one race as well. It adds up fast.

You really do need a fair amount of cash and training time to race these things well. (Or be sponsored!)

Note that these are IRONMAN competitors - a typical triathlete is probably not up to that income /commitment standard.