Calling dispatchEvent(clickEvent) on a textbox doesn’t work

I want to programmatically generate a click event on a textbox when a user clicks on a button. I can see that the textbox gets the event but the focus doesn’t change to the textbox.
What am I doing wrong?

function handleClick(event)
{
    let textbox = document.getElementById('text');
    let rect = textbox.getBoundingClientRect();            

    let newEvent = new MouseEvent('click', {
        clientX: rect.x + 5,
        clientY: rect.y + 5,
        x: rect.x + 5,
        y: rect.y + 5,
        pageX: rect.x + 5,
        pageY: rect.y + 5
    });

    textbox.dispatchEvent(newEvent);
}

<input type="text" id="text" onclick="console.log('clicked')" /> 

<button onclick="handleClick(event)">Click</button>