TTY is only 26 years old. Age wise, she should still be in her prime. Having said that, TTY's best year and most dominant year was 2017, which ironically was the same year she decided to skip the WC. Marin seems to have stabilized her game even more. I don't know if Marin is playing at a higher level than when she won the Olympics or her other 3 WC. But at least versus TTY, Marin seems to have improved in the last 3 tournaments.