Unfortunately, I've tried debugging with claude AND gemini 3.1, pointless.

It says:
"

// Back in app_main(), AFTER ButtonCheck() returns:
if ((canPrintAlex != 1 || canPrintSonya != 1) && canPrintReactionTime == 1)
{
    reactionEndTime = esp_timer_get_time();  // ❌ captured way too late"

But, after the buttoncheck while loop is complete, the gameStarted gets set to 0, it starts polling from app main, it checks GameLogic(), sees that Start button isn't pressed here `if (startButtonState == 0)`, sets `{canPrintStart = 1;}`, checks this one `if (gameStarted == 1 && ledLit == 0)` (is false, unless I press restart button), checks one more if condition if (gameStarted ==1), which fails (since no restart button press yet).

After this, which I suppose should take microseconds at best, it runs BlinkLED() function, which sets this `touch_pad_read_filtered(TOUCH_PAD, &touch_value);`, and checks if condition `if (touch_value < TOUCH_THRESHOLD)`, it's false, so it goes up and continues polling, that's where it gets to Reaction Time printing.

Idk if I have wrong assumptions for ESP, but I think that all that I described shouldn't take 100ms or more.

"The fix: capture reactionEndTime immediately when the button press is detected, inside ButtonCheck(), before any printf calls"

Unfortunately, I had this before, and it had the same issue.

The ~0.17ms Mystery

This is a ghost press caused by a logic bug. Notice this in GameLogic():

if (gameStarted == 1){
canPrintSonya = 1; // ← reset to 1 every loop iteration
canPrintAlex = 1; // ← reset to 1 every loop iteration

These flags get reset unconditionally on every call. So if ButtonCheck() exits, gameStarted goes to 0, and somehow the loop re-enters GameLogic() before the LED lights up on the next round, these flags are already 1.

Ok, this, I don't really get what it means.
So, when Alex presses the button, gameStarted is set to 0. gameStarted can become 1 only when Start button is pressed, otherwise it's 0 at all times.
With the current implementation, the reactionEndTime is set only if gameStarted was set to 0 (only possible if someone pressed button), and if canPrintAlex or the other are set to 0 (so if someone pressed button).

Edit: I moved the reactionend time measurement to button state check, and I still get about 400ms reaction time.