Shiny, I don't think the two are necessarily mutually exclusive. Sure, some of us don't have budgets that would stretch to buying new, but even if we did, would rather buy second hand every time because of how we feel about the issues inherent in a rapacious growth economy.
"New" (on any budget) gives me the heebie-jeebies. What is desirable about more resources and energy having been used so I can enjoy a moment of newness? Because that's all it is, a fleeting point in time, which comes at an unaffordable price, not necessarily for the individual, but for the human collective.
This conversation is so important because it is fraught with assumption and shame. I can't buy new things for myself, my kids or my home. But it never crosses my mind to feel bad about that. Because I don't value 'new'. I actively avoid it in favour of safer, healthier second hand options. To me, that's the crux of it; we are sold this idea of newness as more valuable despite being inherently problematic.
My walls are papered and painted with materials from the reuse shop at the tip, which is also where I have sourced flooring and various fixtures and fittings. My lovely furniture has come from FB, eBay, friends and roadsides. Ditto appliances, kitchenware and technology. Towels, bedding, clothing and footwear for whole family, second hand resale platforms. And no one would ever know, unless I told them. Which I do.
People ask "What if you can't find what you want?" To me, the answer is to not have such a fixed mindset on preference, but to take a more generalist approach. For clothes and footwear, unless specifically looking to buy tailoring or unusual sizing (24W 36L?!), there is a ridiculous amount of choice and almost always possible to find specific branded items in one's size (for example, DC1 has ASC, and for 5 years through primary school had a very strong preference for one particular garment of a particular brand as it didn't trigger any sensory issues. I had no trouble finding this niche garment in increasing sizes, sometimes twice a year, for as long as the preference lasted). If I need to replace curtains, I take my measurements and search eBay intermittently for a few weeks. Then I buy the best I can find -there really is always something nice. When I needed to buy knobs for a chest of drawers where the previous owner had removed the originals prior to sale, I had plenty of choice on eBay - no problem. Most recently, I bought a new doormat which had apparently been an unwanted gift.
Suggesting that people need to check their privilege feels off on this topic; the problem isn't affordability. It is a systemic, insidious indoctrination into a mindset in which the individual is encouraged to seek value in the transient for the benefit of an economic model which exploits, oporesses and degrades.