There are all manner of health conditions that can occur that have little to do with your own healthy living, and don't incapacitate you or make life not worth living, but will cripple you financially.

You might end up with Crohn's or all manner of autoimmune conditions where patented biologics easily costs north of $100k US a year just in medication, but your quality of life if you find a medication that works is not particularly degraded from the average person.

CrossFit will not prevent you from getting into that situation, and I think it would be a vast overreaction to commit suicide in response to such a diagnosis.