Is it true that in Malaysia, Indian = Tamil? What is the classification of others like Punjabis, Malyalis, Telugus, Bengalis etc.

Forgive me if I sound ignorant but I'm genuinely curious. I'm from Australia and was reading another thread where it seems like non-Tamils consider themselves to be too superior to be called Indian, and that Indian basically implies Tamil in Malaysia.

This is a bit surprising, because India is actually a multi-ethnic, multilingual society. Indian refers to descendant of the Indus Valley Civilisation, and all these ethnic groups were historically from the Indus Valley. A DNA test will reveal that that is where the bulk of their DNA is from. As for Punjabis, we're at the heart of the Indus Valley, and we also have the DNA of virtually every ancestral group that forms Indian genetics.