I make my determinations from Scripture.
In the passage you quoted, God was getting Moses acquainted with Him. He was just tending his sheep like he did every day and noticed the bush that was on fire but was not consumed. God got Moses’ attention. The burning bush is not remembered when telling the story. God called Moses there to lead His people.
After that, God gave Moses the Old Covenant of law from Mountain Sinai – the mountain that quaked.
The ground was holy because God’s presence was there.
Under the New Covenant of Grace, people are holy, places are not. God has no shrines upon this earth except the hearts and minds of men and women. There are no holy places. “Do you not know that your body is a temple of the Holy Spirit within you, which you have from God.” He makes his home with me in my body through His Spirit, so that wherever I go He goes. Paul said “glorify God in your body.” Wherever a child of God goes, God is there.
God cannot be boxed in and Thank God, there are no sanctuaries.