So the people who were going to Zion in Psalm 84 did an impossible 1200 mile detour past Mecca.

You clearly don’t understand that this means the valley of weeping.

The Hebrew word baca is related to bakah, which means “to weep.” Baca refers to a type of “weeping” tree; that is, one that drips resin or gum-like tears, such as a balsam, mulberry, or aspen tree. In 2 Samuel 5:23, bakaim is translated as “balsam trees”

The Valley of Baca was probably a literal place located near Jerusalem. The Valley of Rephaim (2 Samuel 5:18) is a possible identification. The Valley of Rephaim is the site of one of David’s victories over the Philistines; the author of 2 Samuel notes that there were balsam trees there (verse 23). Another possibility is that the Valley of Baca is the Valley of Achor (Joshua 7:24), the place of Israel’s trouble where Achan was executed for bringing guilt upon the nation. In the psalmist’s day, pilgrims probably passed through this water-less valley on their way to Jerusalem to worship.

Let us to evaluate the claim that it is Mecca:

v.1 – ‘How lovely is your dwelling place, O Lord Almighty!’
v.3 – ‘… a place near your altar, O Lord Almighty …’
v.4 – ‘Blessed are they who dwell in your house’
v.7 – ‘They go from strength to strength, till each appears before God in Zion.’
v.10 – ‘I would rather be a doorkeeper in the house of my God …’

Does the Kaaba in Mecca have an alter?
Do people live in the Kaaba?

Why would the pilgrims in Psalm 84 make a massive detour to Mecca, as their destination is given as Zion. Mount Zion is one of the hills on which Jerusalem is founded. In the Bible Zion is often used synonymously with Jerusalem (Isaiah 2:2)