Quite an interesting topic.
Is this a new phenomena? Young athletes dying suddenly from cardiac arrest?
Apparently young athletes died from sudden cardiac arrest too before 2019.
Here is a google search: "cardiac arrest in young athletes" with results ranging from the year 2015 to 2019. There are tons of articles about this.
What would be a good and accurate way of determining if that has increased?
Is frequency illusion something to take into consideration?
Can one make a precise estimation by monitoring the mass-media and keeping track of cases and comparing with, what?
Could pre-covid articles about such cases have been planted onto the internet (and Internet Archive) without anyone noticing?
https://web.archive.org/web/20130716061430/https://www.ghsa.net/sudden-cardiac-arrest-athletes
https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.108.804617