`strictNullChecks` short-circuits the subsequent type checks

Bug Report

hello， I encounter a strange bug when I use strictNullChecks: true, and here is an example:

interface A {
  a: number;
}
const list: A[] = [];
list[0] ??= {};  // throw an error: Property 'a' is missing in type '{}' but required in type 'A'
list[0] = list[0] ?? {};  // the type checking not work !
list[0] = list[0] || {};  // the type checking not work !

🔎 Search Terms

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

It seems the type checking works after I close the strictNullChecks options
Playground link with relevant code

💻 Code

interface A {
  a: number;
}
const list: A[] = [];
list[0] ??= {};  // throw an error: Property 'a' is missing in type '{}' but required in type 'A'
list[0] = list[0] ?? {};  // the type checking not work !
list[0] = list[0] || {};  // the type checking not work !

🙁 Actual behavior

list[0] = list[0] ?? {}; doens't throw any errors

🙂 Expected behavior

I expect that list[0] = list[0] ?? {}; should throw an error

Start with the linked TypeScript Playground and reproduce the example with strictNullChecks enabled, comparing ??= with the subsequent ?? and || assignments. Trace the type-checking path for these assignment forms and add or update a regression test showing that assigning an incomplete object reports the missing property error.