yes! 
it depends on how self-serve the product is and how savvy the buyer is. For example, a social media management tool (like Buffer) must leverage PLG because buyers expect a self-serve approach; it’s relatively simple to understand; the price-point is low etc.
If your product is high-complexity, needs implementation support, is new (with limited expertise from buyers), needs a lot of cross-team alignment to purchase, has a high learning curve etc. then it likely will need more of a human touch.
However it doesn’t need to be either PLG or not-PLG; there can be a balance. A human-assisted PLG approach can be very effective – combining prompts inside the product with access to people to answer questions and provide guidance.
Does that answer your question @Logesh?