Olympic gymnast Simone Biles earned $5 million a year in corporate sponsorship deals from a slew of household names including United Airlines, Visa and Uber Eats. Swimmer Katie Ledecky nets $3 million a year from brands such as Adidas and Ralph Lauren, among others. While Biles and Ledecky are celebrity athletes with endorsement deals commensurate with their status, many other U.S. athletes at the 2020 Olympic Games in Tokyo this year relied on side jobs and crowdfunding sites to get there. For every U.S. Olympic superstar …