Bag weight was about 22 Kg. I use a large Osprey wheeled duffel which has a low tare weight, but is tough and drags well across rough ground because of its large wheels. I could have taken a good 1-2 Kg less - eg. I took some long-sleeved shirts, an item of clothing that I essentially never wear - just in case they were needed in the more conservative countries. They weren't needed anywhere. Trousers frequently were.
I have quite a lot of Columbia lightweight, quick-drying shirts, shorts and trousers that are easily hand-washed and dry quickly in just about any situation. Again, I could have taken fewer and washed a little more often. It's a weight/convenience balance.
For the Arctic, I had a long and sleeveless (the latter not really needed) fleece, a windproof North Face hooded jacket and lightweight waterproof jacket and trousers. It was summer, so not bitterly cold. It got a bit wet at times on the Zodiacs. Generally, I run hot and don't feel the cold, so I don't need thermal gear.
I have an aversion to wasting my life shopping, so I essentially don't buy stuff and add to the weight while travelling. Weight is not a problem on the DONEx, but the limitation comes on the el-cheapo whY internal flights, so I operate to the lowest common denominator, sticking at <23 Kg. Interestingly, Air India has a 25 Kg checked bag limit, rather than the common 23 Kg.