How can I change mouse pointer size in Windows?

On my 4k screens, I like to crank up the mouse pointer size in windows.

This is great for 95% of usage, but sometimes I need a small mouse pointer again for finer-precision work.
Unhappy that I have to open settings each time, I want a keyboard shortcut that I can use to toggle between big mouse and small mouse.

So I composed the following in the hope it would do the trick:

1. Update the registry with the new mouse size setting
2. Call SystemParametersInfo() with parameter SPI_SETCURSORS to jog the system to re-read the mouse settings.

Alas, no joy.

Can anyone point out the folly of my ways? Cheers, Dave

Code below:

param([int]$MouseSize=0)

###########################################
#
# DISAPPOINTINGLY  THIS DOES NOT YET WORK
# Need to figure out why
#
###########################################
 
##################
# Constants
##################
 
[int]$small_mouse = 48
[int]$big_mouse   = 80
[int]$min_mouse   = 1
[int]$max_mouse   = 256
 
[string]$path = 'HKCU:\Control Panel\Cursors'
[string]$name = 'CursorBaseSize'
 
##################
# API Import
##################
 
Try{
    [void][SysParams]
} Catch {
Add-Type @'
    using System;
    using System.Runtime.InteropServices;
    public class SysParams {
        [DllImport("user32.dll", SetLastError = true)]
        [return: MarshalAs(UnmanagedType.Bool)]
        internal static extern bool SystemParametersInfo(uint uiAction, uint uiParam, uint pvParam, uint fWinIni);
 
        public static bool RefreshCursor()
        {
            return SystemParametersInfo(0x0057, 0, 0, 0); // SPI_SETCURSORS = 0x0057;
        }
    }
'@
}
 
##################
# Main
##################
 
# Is $MouseSize passed in valid?
if ($MouseSize -ge $min_mouse -and $MouseSize -le $max_mouse) {
    $new_size = $MouseSize
} else {
    # If invalid $MouseSize passed in, toggle current mouse setting
    # First determine if current setting closer to $small_mouse or $big_mouse
 
    $current_size = (Get-ItemProperty $path).$name
    $diff_small = [math]::Abs($current_size - $small_mouse)
    $diff_big = [math]::Abs($current_size - $big_mouse)
 
    if ($diff_small -lt $diff_big) {
        $new_size = $big_mouse # Mouse is small, so toggle big
    } else {
        $new_size = $small_mouse # Mouse is big, so toggle small
    }
}

Set-ItemProperty -Path $path -Name $name -Value $new_size
$resp = [SysParams]::RefreshCursor()