Correct, the perceived colour is not. But objects do have inherent, objective properties that affect how light with wavelengths between 400 and 800 nm interacts with them. And I can quite easily define the colour of an object exclusively in terms of those properties, without perception of any kind being required.
What is colour? Is it an objective property of an object? A measurable property of the light that travels from the object to your eye? A biochemical process involving the photoreceptor proteins in your retina? Or is it merely a sensation in your mind?
You have dismissed out of hand any possibility that the first of these definitions can be useful. But objects do have objective and inherent physical properties, including one that involves the interaction of light and matter to produce reflected light with different relative intensities of different wavelengths. We have a name for that property. It's called colour. And it's an inherent characteristic property of an object.
An apple doesn't stop being red when you stop looking at it. It doesn't stop being red if a colour-blind person looks at it. It doesn't stop being red when both those people leave the room. The physical molecules contained in the skin of apple don't change when you look at it. The energy changes that those molecules undergo when white light shines on them doesn't change when you look at it. The relative intensities of red vs not-red light that reflects off the apple doesn't change when you look at it. The light reflecting off the apple is identical in each case.
Now, what happens when that light gets to your retina is a different thing. What happens when your retina sends a nerve signal to your brain is another different thing. What your brain tells you you're perceiving is a third different thing. Your ability to express what you're perceiving with language is a fourth different thing. And all four of those things might be different for different people, depending on retina and brain and mind and culture.
The apple's still red, though. Because we can define red as "the red light is more intense than the other light", and in that definition the colour of the apple is just about the apple, and has nothing to do with a human retina or a human mind.
"The water is blue" is a true statement, whether or not you're perceiving it to be so. "The water appears blue" is also true, but that second statement involves a very different process, and its truth is not a necessary condition for the first.