What happens to the age cap?
Mexico's U-23 squad would be losing 12 out of its 20 members if the eligiblity is changed

The International Olympic Committee (IOC) has confirmed that the Tokyo 2020 Olympics will be pushed back until next year due to the coronavirus outbreak that has placed the whole world into a state of emergency.

In the Summer Olympics, one of the main attractions is always the men's football tournament which features high-caliber teams and rising stars in a tournament with huge importance, only second to the World Cup. The main difference between both events is the age cap, with the former only allowing players with 23 years of age or lower to participate. This means that for the 2020 tournament, only players born on or after the 1st of January of 1997 would be allowed to participate. 

With the postponement, the question now arises: Will the eligibility also be modified and only players born in 1998 and later will be able to play?  In the spirit of fairness, the initial age cap would have to stick as member associations from all confederations except CONCACAF held their qualifying tournaments with players of that age category. However, the topic poses a serious issue to the North American, Caribbean and Central American federations that haven't even held their qualification for the Olympics, as they would have to discard more than half of the squads they've been preparing in the four-year cycle.

A clear example of teams worried about this situation is Mexico's U-23 National Team who won the gold medal at London 2012. For the CONCACAF Qualifying Tournament, coach Jaime Lozano had called up twenty players, however, with the spread of the virus, the tournament had to be moved back. Out of those twenty players, twelve would be born before January 1st, 1998 including players like Sebastian Jurado, Uriel Antuna, Sebastian Cordova, Carlos Rodríguez and Edson Alvarez; all who have had senior-squad calls.

Article 55 of the men's football tournament at the Summer Olympics talks about unforeseen situations like these ones:

Any matters not provided for in these Regulations and any cases of force majeure shall be decided by FIFA in cooperation with the IOC and Tokyo 2020. All decisions shall be final and binding and not subject to appeal.

Under this article, FIFA and the IOC would be in a position to allow players from 1997 to participate without any issues, but only time will tell if both governing bodies decide to do the right thing and all participants are allowed to play with 24-year-olds.