How is this different from bowing before any other religious symbol?
It depends on the context the person bowing before it takes the religious symbol.
A modern example that keeps popping up is the claim that Catholics are idol worshipers because they pray before their symbols. But the fact is, they do not think of their statues, holy symbols or whtever is God nor a medium of God.
If it is anything(this is my opinion), it is kind of a reference point that identifies them as of the Catholic faith to other Catholics. If they see a catholic praying in another direction, it may cause others to suspect that individuals understanding of their faith.
I am pretty sure that practitioners of Islam would suspect such an individual who claims to be a muslims but do not carry out the proper ritual of pryer with them.
As an atheist(agnostic) I find,unless otherwise directed by them, to at least face the direction of their prayers when I am in a facility controlled by the practioners. To not do this seems like a form of disrespect which is something I do not wish to construe.
Prior to Muhammad’s birth, there were about 570 tribes that comprised the Arab people. These tribes worshipped about 360 gods at Mecca in the Kabah structure.
History records that the first thing that Muhammad did after conquering Mecca was to go to the Kabba and destroyed the 360 idols which were both inside and outside of the structure. ........

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Well yeah. That was a tactical move. As the inventor of the newly created, fascist politico- religious ideology, he wanted no competition for idol worship. That's exactly why he partnered himself with a gawd.
Do you know the slogan that one recites to join the cult of Muhammad?
There is no God but Allah and Muhammad is his Messenger?
It is also an identifier.
There is an identifier for Christians:
Jesus Christ is my Lord and Savior.
Hmmm, the more I think about it, the more I realize that Christians and Muslims are more similar to each other than, say, Christian and Jews