Type Intersection incorrect for optional parameters in functions with exactOptionalPropertyTypes: true. undefined type is flip based off Intersection types

[JDMathew]

This issue seem to only be related when exactOptionalPropertyTypes: true option is set

If I have:

type A = {
  disabled?: boolean;
};

type B = {
  disabled?: boolean | undefined;
};

type C = {
  disabled?: boolean;
};

type AB = A & B;
type AC = A & C;

const fnA = ({disabled}: A) => {
  disabled //disabled: boolean | undefined
};

const fnB = ({disabled}: B) => {
  disabled //disabled: boolean | undefined
};

// case AB is incorrect in this function!
const fnAB = ({disabled}: AB) => {
  disabled //disabled: boolean 
};

const fnAC = ({disabled}: AC) => {
  disabled //disabled: boolean | undefined
};

Consider fnA, since a property that is optional may be undefined when it is called it makes sense that undefined is added to the type, as is in the case in fnA // disabled: boolean | undefined. (fnB example added for completeness).

Now consider fnAB with the intersection type AB, property disabled type should also be // disabled: boolean | undefined but it is not, instead it is // disabled: boolean

Finally fnAC with the intersection type AC, the property disabled type is now correct being // disabled: boolean | undefined.

It seems like in the above example with fnAB (intersection of AB) the undefined's are canceling out since undefined is added with the ? optional parameter. A similar issue can be observed with two undefined such as { disabled?: boolean | undefined; } && { disabled?: boolean | undefined; } would result in //disabled: boolean

It's worth noting this doesn't seem to only be limited to function parameter de-structuring since a similar issue is seen in:

// incorrect
function fnAB(props: AB) {
  props.disabled //disabled?: boolean
}

// correct
function fnAC(props: AC) {
  props.disabled //disabled?: boolean | undefined
}

When exactOptionalPropertyTypes: false property disabled is always disabled //disabled: boolean | undefined which is correct