Why is the wettest place in Eurasia located not in the equatorial but in the subequatorial belt?

The humidity level of a place depends not only on the geographical location of the climatic zone, but also on the terrain. If the relief is flat, then rain clouds are carried by the wind through these places without obstacles and precipitation falls evenly. But when the clouds reach the highlands, they can no longer move forward, and all precipitation falls at the foothills of the mountains (in the case of Eurasia, at the foothills of the Himalayas). Therefore, in the equatorial climatic zone of Eurasia, which is located on flat terrain, precipitation is less than in the subequatorial zone.