It's actually far less in IT. A close relative worked in construction. You think tech has bad harassment issues? Construction had open prostitution at work, rape jokes targeted towards the female engineers, and some people would urinate openly.

Anything with undereducated people are also quite toxic. Both the managers and colleagues often have very low willpower and get emotional over small issues, starting fights for small things, like not getting them a drink, or touching their car.

In tech, people are not so replaceable, so most companies have plenty of financial incentive to treat each other respectfully.

Startups can be a little worse than usual, because the people are younger and there's more of a "college" climate.