Prevent duplicate queries and N+1 problem in Laravel collection

I'm currently working on a simple Laravel project where I need to get the posts of the users I'm following. With the code below, I can get the posts but I also add a lot of duplicate queries and an N+1 issue on the Authenticated user. So it's becoming sort of a head scratcher. I've looked though other similar scenarios online but I haven't been able to pinpoint what I'm doing wrong. Perhaps there is a better way. Currently, I have on the User model:

public function usersImFollowing()
{
    return $this->belongsToMany(User::class, 'follow_user', 'user_id', 'following_id')
        ->withPivot('is_following', 'is_blocked')
        ->wherePivot('is_following', true)
        ->wherePivot('is_blocked', false)
        ->paginate(3);
}

public function userPosts()
{
    return $this->hasMany(Post::class, 'postable_id', 'id')
        ->where('postable_type', User::class);
}

As you can see, I am using two booleans to determine if a user is following or is blocked. Also, the Post model is a polymorphic model. There are several things I've tried, among them, I tried a hasManyThrough, without using the hasMany Posts relationship above. It got the posts for each user but since I'm using the booleans above, I couldn't use them in the hasManyThrough, it simply got the posts based on the following_id, whether or not the user was following or was blocked became irrelevant.

Then in a separate service class, I tried the methods below (I'm using a separate class to maintain the code easier). They both get the posts for each user but add an N+1 problem and 12 duplicate queries based on 5 posts from 2 users. I will also need to filter the results based on some conditions, so it will probably add more queries. Additionally, I'm using a Laravel resource collection that would pull other items for each post, such as images, comments, etc., so the amount of queries would increase even more. Not sure, perhaps I'm doing too much and there is an easier way:

Either:

$following = $request->user()->usersImFollowing();
    $posts = $following->map(function($user){
        return $user->userPosts()->get();
    })->flatten(1);
    return $posts;

Or

$postsfromfollowing = [];
    $following = $request->user()->usersImFollowing()->each(function($user) use (&$postsfromfollowing){
        array_push($postsfromfollowing,$user->userPosts);
    });
    $posts = Arr::flatten($postsfromfollowing);
    return $posts;

Maybe you could use scopes to do little celanup of code and generated sql.

In User model something like

public function scopeIsFollowedBy(Builder $query, int $followerId) {
  return $query->where('following_id', '=', $followerId);
}

And in Post model

public function scopeIsFollowedBy(Builder $query, int $followerId) {
  return $query->whereHas('user', function($q) use ($followerId) {
    $q->isFollowedBy($followerId);        
  });
}

You can use it then in coltroller like any other condition like this:

Post::isFollowedBy($followerId)->...otherConditions...->get();

The SQL generated won't go through foreach but only add one IF EXISTS select (generated by whereHas part of the code)

More on local scopes in Laravel is here https://laravel.com/docs/8.x/eloquent#local-scopes