If I were an epileptic, I would appreciate seeing the warning before I buy the game, not once I've launched it. Which, by the way, invalidates Sony's return policy.
Do you think epileptics really need to be told every single time they start the game? I’d bet they’re as annoyed as non epileptics.
I drop and pick games back up after a long time very frequently, I'd certainly appreciate it if I were affected. Plus, what about borrowed/Steam family shared/whatever games?
I'm not a console player (or an epileptic), does Sony's storefront really not tell you about health warnings?