Remaking is difficult or easy, that is a big debate topic. Remaking any film means trying to re-produce, a film from different language or an old classic from same language.
Copying is all about executing the same stuff from original without paying any copyrights amount or giving due credit. If you admit it as an "inspiration", then you have to give a theory to support your claim.
Remakes are common, taking a novel and making it on screen is called adaptation to the screen. Writing a story based on a scene, dialogue or storyline of another film is called Inspiration, if due credit is given.
If same writer uses his scene or dialogue or storyline again, then he can say it as Expanding on an original or inspirered idea and he can also say it re-exploration.
So, remaking a film is all about paying copyrights, giving due credits, taking permission from the original writers and then re-producing it as it is or changing it completely or tweaking it.
When Harish Shankar tried to say that everything is a remake of something or the other, one feels, it is easy to agree that they remade a film than just say it is common. No one is being convicted for making a film as a criminal.
A filmmaker doesn't have to always claim that they make original ideas only. If some people give less credit, then they should be informed about the hard work and process behind filming than such statements, which reduce our own reputation.
Hope, we can see that at least other filmmakers try to understand what we are saying. We don't have anything against Harish Shankar or anyone, please do remember that as well.