How to test if a button is conditionally enabled in React Testing Library / Jest

Question

I need to test if a button is conditionally enabled after text inputs are filled out.

Right now simply checking to see if they are disabled works with the following:

expect(screen.getByTestId('select-service-btn').closest('button')).toBeDisabled();

But I want to check if they get enabled after input values are filled out.

This is what I currently have.

it('Should test to see if a button gets enabled when forms are filled out', () => {
    const firstInput = screen.getByTestId('firstName-input');
    const lastInput = screen.getByTestId('lastName-input');
    const emailInput = screen.getByTestId('email-input');

    expect(screen.getByTestId('select-service-btn').closest('button')).toBeDisabled();

    fireEvent.change(firstInput, {
      target: { value: 'test content' },
    });

    fireEvent.change(lastInput, {
      target: { value: 'test content' },
    });

    fireEvent.change(emailInput, {
      target: { value: 'test content' },
    });

    expect(screen.getByTestId('select-service-btn').closest('button')).not.toBeDisabled();
})

I want to say this would check to see if a button is disabled, mimic filling out the necessary inputs, and then check to see if the button changed from disabled to enabled. But the test fails.