I haven't heard this particular Baba Ramdev remedy, though I don't think he'd suggest olive oil - he'd pick something native.

Part of the issue in the Indian middle class (with presumably similar things in Pakistan) is the strong desire to find wisdom in old folk remedies. I can't begin to count the number of WhatsApp forwards early in the pandemic touting gargling with salt water as a means to combat the virus. That, or nigella seeds, ginger, tulsi, ghee, etc.