Why array element is treated as proxy as raise error when mapping it?

In Laravel 8 / livewire 2.5 / alpinejs 3 application I make context menu for listing of data
and to show only 1 context menu on server side I senerate on server side array :

foreach( $this->newsDataRows as $nextNewsDataRow ) {
    $this->selectedNews[$nextNewsDataRow->id] = false;
}

in blade file :

selectedNews: @json($selectedNews),

and condition for context menu :

 <div class="show_context_menu_container" x-show="selectedNews[{{$news->id}}]"

 

Problem is that when context menu is selected and operation completed I trigger event to set all elements of
selectedNews into false :

window.addEventListener('hideAllSelectedNewsItems', event => {
    console.log('hideAllSelectedNewsItems::')
    console.log( this.selectedNews )

    this.selectedNews.map((nextSelectedNews, index) => {
        console.log('nextSelectedNews::')
        console.log(nextSelectedNews)
        this.selectedNews[index]= false
    })

})

  

But I got error : https://prnt.sc/YKDvN_MfbYBN
I wonder why this.selectedNews is treated as proxy and in which way it can be fixed ?

Thanks!