SharePoint Online: Change Navigation Settings using PowerShell

#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Taxonomy.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Publishing.dll"
   
#Config Parameters
$SiteURL= "https://crescent.sharepoint.com/sites/marketing/2018"

#Get Credentials to connect
$Cred = Get-Credential
 
Try {
    #Setup the context
    $Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($SiteURL)
    $Ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.UserName,$Cred.Password)
   
    #Get the Web
    $Web = $Ctx.Web
    $ctx.Load($Web)
    $Ctx.ExecuteQuery()

    $TaxonomySession = [Microsoft.SharePoint.Client.Taxonomy.TaxonomySession]::GetTaxonomySession($Ctx)
    $NavigationSettings = New-Object Microsoft.SharePoint.Client.Publishing.Navigation.WebNavigationSettings($Ctx, $Web)

    #Set Both current and global navigation settings to structural - Other values: PortalProvider,InheritFromParentWeb ,TaxonomyProvider
    $NavigationSettings.GlobalNavigation.Source = "PortalProvider"
    $NavigationSettings.CurrentNavigation.Source = "PortalProvider"

    #Show subsites in Global navigation
    $Web.AllProperties["__IncludeSubSitesInNavigation"] = $True

    #Show pages in global navigation
    $Web.AllProperties["__IncludePagesInNavigation"] = $False

    #Maximum number of dynamic items to in global navigation
    $web.AllProperties["__GlobalDynamicChildLimit"] = 15

    #Update Settings
    $Web.Update()
    $NavigationSettings.Update($TaxonomySession)
    $Ctx.ExecuteQuery()

    Write-host -f Green "Navigation Settings Updated!"
}
Catch {
    write-host -f Red "Error Updating Navigation Settings!" $_.Exception.Message
}