Yeah, no matter how talented you are at football, if you're even more talented and interested in something else, it's probably better to do that.

In Belgium, we have Remco Evenepoel as a very good example of that. Former youth player at RSC Anderlecht and the Belgian national team, who went into cycling at age 17 (his father was a professional cyclist).

Here, https://en.wikipedia.org/wiki/Remco_Evenepoel#Career_achievements , just look at this guy's achievements. Became a Belgian, European Champion and World in cycling, in 2018, a year after quitting football, both for road races and time trial.

In other words, Splinter de Mooij might leave football, he might become one of the greatest doctors ever nonetheless.