Hi Taryal
During Metta Bhavana, you can look at things the other way. You can see how people are trapped in this suffering due to their ignorance. You can contemplate the suffering they endure because of their ignorance. From here you can then you would sincerely want all beings to be free from suffering, because there is so much to endure. Think about it, if all beings are already Arahants/ sotapannas then there is no need to wish them to be free from suffering! Ultimately, Metta Bhavana is about the intention.
7. What matters is not the particular set of words used, but what is felt in one’s heart. In order to do that one needs to truly comprehend that there is REAL SUFFERING in this world, not only at the human or animal realms but in many other realms. (5. Ariya Metta Bhāvana (Loving Kindness Meditation)
Again, what’s important is to understand that an infinite number of beings are going through suffering, and you wish they can be rid of it. Just like how you can generate compassion from seeing a starving child, the same can be done with Metta Bhavana.