Django N duplicated queries

#models.py

from django.db import models
from mptt.fields import TreeForeignKey
from mptt.models import MPTTModel


class Genre(MPTTModel):
    name = models.CharField(max_length=50, unique=True)
    parent = TreeForeignKey('self', on_delete=models.CASCADE, null=True, blank=True, related_name='children')

    def __str__(self):
        return self.name


class Game(models.Model):
    name = models.CharField(max_length=50)
    genre = models.ManyToManyField(Genre, blank=True, related_name='games')

    def __str__(self):
        return self.name

# settings.py
INSTALLED_APPS = [
    ...
    'debug_toolbar',
    'mptt',
    'rest_framework',
    'rest_framework_recursive',
    'games',
]

# views.py
from django.shortcuts import render
from rest_framework import serializers
from rest_framework.response import Response
from rest_framework.views import APIView
from rest_framework_recursive.fields import RecursiveField

from games.models import Game, Genre


class GameSerializer(serializers.ModelSerializer):

    class Meta:
        model = Game
        exclude = ['genre', ]


class GenreGameSerializer(serializers.ModelSerializer):
    children = RecursiveField(many=True)
    games = GameSerializer(many=True,)

    class Meta:
        model = Genre
        fields = ['id', 'name', 'children', 'games']


class GamesByGenreAPI(APIView):
    queryset = Genre.objects.root_nodes()
    serializer_class = GenreGameSerializer

    def get(self, request, *args, **kwargs):
        ser = GenreGameSerializer(data=Genre.objects.root_nodes()
                                      .prefetch_related('children__children', 'games'), many=True)
        if ser.is_valid():
            pass
        return Response(ser.data)

# populator.py

import standalone
standalone.run('myproject.settings')

from games.models import Game, Genre

gen_action, _ = Genre.objects.get_or_create(name="Action")
gen2, _ = Genre.objects.get_or_create(name="Shooter", parent=gen_action)
gen3, _ = Genre.objects.get_or_create(name="Stealth", parent=gen_action)
gen_simulation, _ = Genre.objects.get_or_create(name="Simulation")
gen5, _ = Genre.objects.get_or_create(name="Vehicle Simulation", parent=gen_simulation)
gen6, _ = Genre.objects.get_or_create(name="Construction Simulation", parent=gen_simulation)
gen_sports, _ = Genre.objects.get_or_create(name="Sports")
gen8, _ = Genre.objects.get_or_create(name="Racing", parent=gen_sports)
gen9, _ = Genre.objects.get_or_create(name="Sports Games", parent=gen_sports)


x, _ = Game.objects.get_or_create(name="Battlefield")
x.genre.add(gen2)
x, _ = Game.objects.get_or_create(name="Destiny 2")
x.genre.add(gen2)
x, _ = Game.objects.get_or_create(name="Apex Legends")
x.genre.add(gen2)


x, _ = Game.objects.get_or_create(name="Invisible")
x.genre.add(gen3)
x, _ = Game.objects.get_or_create(name="Hitman")
x.genre.add(gen3)
x, _ = Game.objects.get_or_create(name="Dishonored 2")
x.genre.add(gen3)


x, _ = Game.objects.get_or_create(name="MS Flight Simulator")
x.genre.add(gen5)
x, _ = Game.objects.get_or_create(name="Euro Truck Simulator 2")
x.genre.add(gen5)
x, _ = Game.objects.get_or_create(name="Bus Simulator 21")
x.genre.add(gen5)


x, _ = Game.objects.get_or_create(name="SimCity")
x.genre.add(gen6)
x, _ = Game.objects.get_or_create(name="Theo Town")
x.genre.add(gen6)
x, _ = Game.objects.get_or_create(name="Design Home")
x.genre.add(gen6)


x, _ = Game.objects.get_or_create(name="Forza Horizon 5")
x.genre.add(gen8)
x, _ = Game.objects.get_or_create(name="Asphalt 9")
x.genre.add(gen8)
x, _ = Game.objects.get_or_create(name="Dirt 5")
x.genre.add(gen8)

x, _ = Game.objects.get_or_create(name="FIFA 21")
x.genre.add(gen9)
x, _ = Game.objects.get_or_create(name="NBA 2K22")
x.genre.add(gen9)
x, _ = Game.objects.get_or_create(name="Madden NFL 21")
x.genre.add(gen9)


# pip freeze
asgiref==3.4.1
backports.zoneinfo==0.2.1
Django==4.0b1
django-js-asset==1.2.2
django-mptt==0.13.4
djangorestframework==3.12.4
djangorestframework-recursive==0.1.2
pytz==2021.3
sqlparse==0.4.2
standalone==1.0.1