Isn’t the main point of having a corporation as a legal entity to replace personal liability with corporate liability?

Only some liabilities. Mainly debt -- so people would not be afraid to start businesses and borrow money. But if, say, an accountant produces an incorrect report -- they may personally go to jail. Or an HR or information security officer can be accused of negligence.

Sometimes it even works the other way, a person (usually Officer) can be personally responsible for company actions, even when they didn't commit it themselves. Logic is they should've known or implemented processes in a way to prevent it in the first place. People often don't realize how much responsibility officers carry for the actions of their employees they have little control over.

Also https://en.wikipedia.org/wiki/Piercing_the_corporate_veil

Corporations cannot replace some regulated liability, for example some types of professional engineers.