This is not the most comfortable weather, but it is a darn site better than that in many of the boating areas which I follow. For example, England has been in the deep freeze for more than two weeks. Boaters there are having to deal with ice-covered waterways and frozen pipes. Here it is just rain. But relentless rain.
Nevertheless, to me this is a huge advantage.
Living aboard in the winter is difficult. The boat must be kept warm, else frozen water lines, valves, tanks, etc are the result. This may not be as easy as you might imagine because boats are not nearly as well insulated as houses are, and the water plumbing may be routed near to the hull. In fact, the plumbing could run behind closets - closets stuffed full of clothing which serve as insulation to keep the interior of the boat warmer... and the water lines colder.
We may get wet walking down the dock, but we don't need to shovel it. The little snow Seattle does get is "self-shoveling" if you just have a little patience. This is a climate where they talk about "bitter cold" and say to keep your pets indoors if the temperature goes below 32 °F. Coming from Spokane, and worse yet, Chewelah (where we once spent two weeks with the daytime highs at -20 °F, nite time lows of -45 °F to -50 °F - the ground was frozen 5 feet down) this is ludicrous. But it is a wonderful ludicrous. We might complain about having to scrape our windshields once in a while, but you will never hear about anyone freezing an engine block.
Look, let me put it this way: There are not many days when we can use the cockpit as the refrigerator annex - it's just too warm out there.
Me and my symbiotic mildew, we're good with that.