Mmmm. there is a lot of 'technical' clothing around - various synthetics designed for outdoor pursuits. Whilst Gore-tex and ir's relations have their fans (especially if children and vast amounts of laundry are involved), there is nobody who can persuade me that organics have come to the end of the line. No amount of fleeces can begin to compare to wool...although even buying a simple jumper can be an ethical and environmental minefield. I do not wear merino or cashmere because of various husbandry issues (such as mulesing and some brutal harvesting of yarns (notably angora). Not would I wear synthetic fibres. Alpaca, while warm, is not very durable but British wool, from black-faced Leicester, Wensleydale or Shetland sheep is stupendous. Wool from the Peruvian highlands, Iceland, Finland, Norway etc. can also be a good choice. For lighter wear or thermal underlayers, silk is, to my mind, better than merino base layers and takes colour without the intensive chemical processes recquired for cotton and other cellulose based yarns (linen, bamboo, hemp etc.). Anyway, there is a whole debate around the brutalities of fast fashion but at the very least, it would be my choice to buy with longevity in mind. Also, good wool (with natural lanolin) does not need washing.
My daughter bought some cotton jumpsuit thingy for £12 - bad enough...but when she announced she was buying one in every colour, I put the phone down on her because this is wrong on so many levels.