Garuda isn't only considered stronger than Devas, He actually is stronger than Devas. His feats speaks for himself.
He alone fought and defeated all the Devas including Rudras and Vasus:
Thus, Garuda brought complete turmoil to the world of the gods. He ripped the gods apart with his wings and beak. Then, the god with the thousand eyes commanded Vayu, “O Marut! It is your duty to drive the dust away.” Then the mighty Vayu drove the dust away. ‘When the darkness had disappeared, the gods attacked the bird. He roared in the sky, like a giant cloud, terrifying all beings. Attacked by the army of the gods, the immensely valorous king of the birds, the destroyer of enemies, rose into the sky, above the heads of the gods. Led by Indra and armoured, they attacked him with many weapons like lances, iron clubs, spears, maces, many sharp swords and chakras as radiant as the sun. Attacked from every side, the king of birds didn’t even tremble. Vinata’s powerful son fought a tremendous battle, showing no signs of tiring out. Like the roar of thunder in the sky, Vinata’s powerful son attacked the gods from all sides with his wings and breast and scattered them in all directions. Oppressed and mangled by Garuda’s beak and talons, a lot of blood flowed from the bodies of the gods and they fled. Overcome by the lord of birds, the Sadhyas with the Gandharvas fled eastwards, the Vasus with the Rudras towards the south, the Adityas towards the west, and the twin Aswins towards the north. Gifted with great energy, they retreated fighting, looking back every moment on their enemy.
Even Indra’s Vajra is nothing infront of him, When Indra Hurled Vajra at Garuda, He easily tanked it and was laughing at Indra.
Garuda, was coursing through the air after wresting the Amrita, Indra hurled at him his thunderbolt. Then Garuda, the lord of birds, struck with thunderbolt, spake laughingly unto Indra engaged in the encounter, in sweet words, saying,'I shall respect the Rishi (Dadhichi) of whose bone the Vajra has been made. I shall also respect the Vajra, and you also of a thousand sacrifices. I cast this feather of mine whose end you shalt not attain. Struck with your thunder I have not felt the slightest pain.'And having said this, the king of birds cast a feather of his.
The only reason, He allowed the thunderbolt to touch his body and he didn't thrashed Indra cause of Respect for the weapon and the deity.
I think it's enough to say, That Lord Garuda is in a league of his own compared to the Devas. Remember Garuda is best among birds as said by Lord Krishna in Bhagavad Gita.