If the intended meaning of "qunūt" in this verse is "obedience", then why has the verse generalised to all of creation even though many of them are not obedient to Him?

Imām Ibn al-Jawzī (d. 597/1201) summarized the scholars' opinions in his book "Zād al-Masīr" as follows:

1. The apparent meaning is general, but the intended meaning is specific: It means all the people of obedience are obedient to Him.
2. The shadows of the disbelievers prostrate to Allah in the mornings and evenings, thus they are considered obedient in that sense.
3. Every creature is obedient in terms of the effect of Allah's creation upon it and His decrees over it, which indicates their submission to the Lord.

These answers were mentioned by Ibn al-Anbārī.