Rails 5.2.8 where clause values are not appending to the AR query

I am facing some problem after trying to upgrade from Rails version 4.2.0 to 5.2.8. Please let me know is there any problem, or why it happened with AR?

class Product < ApplicationRecord

  has_many :product_categories_products, :dependent => :destroy
  has_many :categories, through: :product_categories_products, class_name: "ProductCategory"
  belongs_to :site

  class << self
    def active_products(site, store = true)
          products = store ? self.not_flagged : self.unscoped
         products.eager_load(:categories).where(site: site).order(updated_at: :desc).active.friendly

class ProductCategory < ApplicationRecord

  belongs_to :site, inverse_of: :site_product_categories
  has_many :product_categories_products
  has_many :products, through: :product_categories_products


class ProductCategoriesProduct < ApplicationRecord
  belongs_to :product
  belongs_to :category, foreign_key: :product_category_id, class_name: "ProductCategory"

    @products = Product.active_products(@site, @shopfront)
    @products = @products.where(product_categories: {id: @category.id})

From the above Rails 4.2.0 - It is able to generate the SQL query like below.

 Select * FROM "products" p
LEFT OUTER JOIN "product_categories_products" pcp ON pcp.”tenant_id" = 2 AND pcp.”product_id" = p.”id" 
LEFT OUTER JOIN "product_categories" pc ON pc.”tenant_id" = 2 AND pc.”id" = pcp.”product_category_id" AND pcp.”tenant_id" = p.”tenant_id" WHERE p.”tenant_id" = 2 and products.site_id = 49285 and products.status = 1 and pc.id = 151

From the above Rails 5.2.8 - It is able to generate the SQL query like below.

category ID is not appending to the active_products query.

select * FROM "products" 
LEFT OUTER JOIN "product_categories_products" ON "product_categories_products"."tenant_id" = 2 AND "product_categories_products"."product_id" = "products"."id" 
LEFT OUTER JOIN "product_categories" ON "product_categories"."tenant_id" = 2 AND "product_categories"."id" = "product_categories_products"."product_category_id" AND "product_categories_products"."tenant_id" = "products"."tenant_id"
 WHERE "products"."tenant_id" = 2