Not very long ago, we thought that "life" was due to a non-material life-force thought to inhabit biological entities and thus raise what would be a biological machine to the status of living being.

The Occam's Razor-logic of looking for the simplest explanation possible leads me to the hypothesis that consciousness will similarly turn out to be an emergent property of the mechanical universe [1]. It may be hard to delineate, just as life is (debates on whether a virus is alive, etc.) but the border cases will be the exceptions.

Current research on whether plants are sentient supports this, IMO. (See e.g. "The Light Eaters" and Michael Pollan's new book on consciousness, "A World Appears".)

Meditation adds to this sense. We do not control our thoughts; in fact the "we" (i.e. the self) can be seen to be an illusion. Buddhist meditation instead points to general awareness, closer to sentience, as the core of our consciousness. When you see it that way, it seems much more likely that something equivalent could be implemented in software. (EDIT to add: both because it makes consciousness seem like a simpler, less mysterious thing, but also once you see the self as an illusion, that thing that dominates your consciousness so much of the time, it seems much less of a stretch for consciousness itself to be a brain-produced illusion.)

[1] To be clear, the fact that life turned out to not be a mystical force is not direct proof, it is an argument by analogy, I recognize that.

It is irrelevant whether consciousness is an "illusion." The hard problem of consciousness is why there's any conscious experience at all. The existence of the illusion, if that's what you choose to label it, is still equally as inexplicable.

Of course science may one day be able to solve the hard problem. But at this point in time, it's basically inconceivable that any methodology from any field could produce meaningful results.