A country dominating an event shouldn't matter as the us wins some swimming relays every 4 years. Because they have a huge swimming program and can get the good swimmers for all the relays and abolishing some swimming events for non competitiveness is not addressed.
siwmming is dominated by US and Australia, even Figure Skating before singles were dominated by the US and pairs/dance by Soviets
also gymnastics is one of the main attractions in Olympics and sells tickets , based on London, RG stadium was fully booked unlike wrestling
so I don't think its going anytime soon.