You still can't call that a meaningful organism. The speed of light still means it can't have had more than a few dozen "clock cycles" since the galaxy stabilized enough to permit it, and it doesn't have all that many more "cycles" before the galaxy will be too dead to sustain it. There is no activity it could set itself out to do and then actually do it that would not be literally at least tens of thousands of years behind the stimulus that produced it, and that would be an incredibly quick reaction. There is no force of "evolution" or anything else that could drive this entity. It's just not useful to model it as an "organism".

Even human society can only be analogized to an organism. It isn't one either. It's not enough to point out there's vague similarities but ignore the multiple-orders-of-magnitude differences in the various scales.

And there's no need for "everything to be an organism". There's no physical reality to that idea. It's merely a reflection of our own predisposition towards weak analogical thinking when we should be dealing with things on their own terms. For human society, analogical thinking can easily lead us astray; for galactic scale society it's even harder to get away from analogical thinking because there isn't one (so far as we know) from which we can derive any observations at all, so there's no concrete facts in which we can ground our thinking.

As a stepping stone, "human society as an organism" may be the beginning of understanding. But when you start doing things like bemoaning its lack of self-preservation instinct, it's a sign you've gone too far with the analogy at the expense of dealing with what is really there.