"export = { }" vs "let a = { }; export = a", causes discrepancy in import behavior

TypeScript Version: 3.9.5

Search Terms: I searched import related bug labels

Code

//module a
export = {
  name: 'zzxoto'
};

//module b
const EX = { name: 'zzxoto' };
export = EX;



//////////////////////////////////////////////////////////////////
//when importing a

//this gives error:
//This module can only be referenced with ECMAScript imports/exports by turning on the 'esModuleInterop' flag and referencing its default export.ts(2497)
import { name } from './a';

//this works
import A from './a';
A.name;
//////////////////////////////////////////////////////////////////



//////////////////////////////////////////////////////////////////
//when importing b

//this works
import { name } from './b';

//this works too
import B from './b';
B.name
//////////////////////////////////////////////////////////////////


//tsconfig.json
{
  "compilerOptions": {
    "target": "ES2019",
    "module": "commonjs",
    "strict": false,
    "strictNullChecks": true,
    "allowJs": false,    
    "esModuleInterop": true
  },
  "include": ["**/*.ts"]
}

Expected behavior:
There should be no descrepancy while import module a vs module b.

Actual behavior:
Described above.

Reproduce the discrepancy using modules a and b from the report with TypeScript 3.9.5 and the provided tsconfig.json. Compare named and default imports under esModuleInterop, then verify that equivalent export forms produce consistent import behavior.