Why do fighters like Tyson, Frazier, Hatton, etc not use the straight right

[AlexKid]

Those guys fight in close distance. They don't use range. Straight right, as you can imagine, is less effective in close range, so a close-distnace fighter will use mostly hooks.

a straight right is not so good at close range unless you have short arms, so this doesn't make sense to me yet,

[BattlingNelson]

All three of those guys threw straight right hands. I don't know what you're talking about.

Exactly. Tyson and Frazier also used the jab.