How could I clean up this livewire component?

The code:

<div>
    <select name="tags[]" id="tags" multiple
        class="select2 mt-1 w-full block rounded-md bg-gray-100 border-transparent hover:border-gray-500 hover:bg-white hover:ring-0">
        @if (old('tags'))
            @foreach (old('tags') as $oldtag)
                <option value="{{ $oldtag }}" selected>{{ $oldtag }}</option>
            @endforeach
        @else
            @isset($post)
                @if ($post->tags()->count() > 0)
                    @foreach ($post->tags as $singleTag)
                        <option value="{{ $singleTag->text }}" selected>{{ $singleTag->text }}</option>
                    @endforeach
                @endif
            @endisset
        @endif
    </select>
    @if ($errors->has('tags'))
        <small class="text-red-600">{{ $errors->first('tags') }}</small>
    @endif
</div>

**select2 script init below inside @push('scripts')**

It is a livewire component that takes in an optional parameter named $post.
The reason I have else-isset-if is because, if you "edit" a post, the $post parameter gets that post object but if you "create" a new post, there's no post object to load up in the component. That way laravel still tries to read $post->tags()->count() which will throw an error stating "null" has no method called tags().

That's why I've added the isset part.

It works but also looks extremely ugly. I have absolutely no idea what to do with it.

You might consider migrating your conditional logic into a Livewire computed property instead:

public function getTagOptionsProperty() {
  $old = request()->old('tags');

  return $old ?? $this->post->tags()->pluck('text')->toArray();
}

Then, inside of your Blade view:

@foreach($this->tagOptions)
  {{-- ... --}}
@endforeach

Your markup seems to be mixing Blade attributes with Livewire properties, so I'm not entirely sure what's going on here, but there would seem to be a good opportunity for refactoring.