Not really. The Scythian invaders conquered northwestern India but instead of invading the east they invaded the Deccan but the Scythian invaders were defeated by the Satavahana Dynasty. The Arabs also invaded the Deccan after conquering northwestern India but the Arabs were also defeated by the Chalukya Dynasty of southern India.
Only the Turkic invaders invaded the Deccan after having conquered whole northern India. The Turks of the Delhi Sultanate were able to raise huge armies because of the resources of northern India and thanks to the newly converted Indian Muslims and they invaded southern India but the Turkic invaders of the Delhi Sultanate were defeated by the Vijayanagara Empire.
Even the Mughals invaded southern India with one of the largest armies in the world but even they were repelled by the Maratha Empire.
I gave you the reason why they were defeated.
More over Scynthians known as Sakas had similar culture as of others in North India. Since Mahabharat Happened.
Everheard of Sakyamuni?? Is the other name of Siddharth Gautam!!
So you need not to bring this crap.
Secondly, Arabs faced many blows from both Northern And southern Empires. One empire fell other struck , then another rose, that's how Arabs and Turks invaders were also in constant hits by Northern empires before they reached south.
The defeat is currently the area called Pakistan where muslims are in Majority. That happened due to British secretly supporting Mughals and turks to weaken Northern Empire.
You need to understand the term strategic response before making stupid statements.