The Scorpios YOU are referring to are not that way because of their Sun in Scorpio.
Astrology is very complex and the Sun sign is only a very small part.
And astrology is ONLY an influence on you IF you don't develop self-awareness and try to change yourself.
I have known many people with Sun in Scorpio over my 69 years here. And had many clients with Sun in Scorpio in the 40 years I did in-person readings.
I was married to someone with Sun in Scorpio for 15 years. In his chart, Sun was not very strong .. his 3 planets in Sagittarius, his 3 planets in Libra, and the T-square with Venus in Libra in the 1st house being the "focal planet" .. there were all much stronger than his Sun which was in Scorpio.
He was normal. Wanted everyone to like him and would give freely of his time and assistance to help even strangers (Venus as focal planet wanted everyone to like him).
He never lost his temper .. stellium of 3 planets in Sagittarius. COULDN'T get angry even when he should have.
So you see . .you have to look at the entire chart.
If you only look at the Sun sign, you are misunderstanding astrology and the person too.
Always work only from the individual's birthchart, using the day-mo-yr of birth, the minute-hr of birth, and the birthplace.
There is no other way to use astrology and come up with valid conclusions.
As I said, the particular Scorpio(s) you are referring to are this way either because of other complex issues in their unique personal birthchart . .and/or because of life-experiences which have produced great inner pain resulting in anger, and not having any guidance for learning how to handle their emotions.
An astrologer since 1972, with a degree in psychology.