There are definitions that actually fit with modern neuroscience and can be evaluated.

Your choice to choose a definition that doesn't align with modern knowledge is not evidence that it's undefinable.

The two most popular ones are a sense of self as separate from the environment.

Another is the ability to be able to predict the environment and plan or adjust plans accordingly.

Another is sensory binding to experience a unified perception.

All of these can be evaluated objectively and investigated for mechanisms. They all have a ton of research on them.

Your definition was something you came up with on the fly to see what I would say. And that's fine.

But I explained why this definition is flawed.

Even so. It can also be objectively measured and has been extensively researched as to its mechanisms.

So even if that was what consciousness is, we do have theories and research , at present, to explain how it works.