This bug has been outstanding for many years. Workarounds:
1. Set Preferences > Interface > Font Size to Automatic and the Windows Display Settings > Scale And Layout to 100%. Dragging photos to the map and the Develop eye dropper then become accurate for most people. But if the fonts are now too small, adjust the Windows Display Settings scaling, not the font size in LR. (That works for some but not all people.)
2. Instead of dragging to the map, right-click the map location and do
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