Anecdotally, I've heard that there's a strong link between heavy boozing and suicide, especially via firearm. One wonders if it's determined people needing courage, or drunk people becoming determined.
The GP asked "Who decides on the duration of the waiting period? Why can’t people be in charge of their own lives?"
And the OP is making that point that (a) there must be someone in a position to make that decision, and that (b) there must be some waiting period.
In fact, if as you imply there are no countries that allow walk-in assisted euthanasia, that's a point in favor of the OPs point, because it suggests that we do widely recognize that there have to be some limits to individual freedom in this area.
Are you saying if someone buys a rope and ties a noose, then lets it sit there for at least 90 days, then they can use it to hang themself after a bad day and that's not suicide in reaction to the bad day?
Perhaps it'd be best to circle back and check the actual specifics?
That tends to not be what happens-- instead, the correction is used as a rebuttal against people who don't like it, but the correction and its implications aren't considered by people who liked how the story went in the first place. Even now, that comment is the top one in this thread, and it has not been edited to add any additional clarification or corrections.
If you walk in very drunk asking to be euthanised, one would hope that they would have to wait until you are no longer drunk to confirm you really want to be euthanised. Then, who decides on the waiting period?
Likewise if a traumatic event clouds your judgement (as some events can do), it's not unreasonable to make you wait until your judgement is sound. Then someone has to decide on the waiting period.
Potentially this can be studied statistically. Just collect data regularly after an event (such as binge drinking event) to evaluate how quickly people's judgement stabilises. That way we may find that the death of a spouse doesn't cloud the judgement, in which case the waiting period is 0.