In brief - It's complicated; there's no actual 'shortage' of wool; what there was (and to some extent still is) , is a disruption to the global wool market and supply chain and, leading on from that, a shortage of the 'right' sort of wool - or at least, what is nowadays considered to be the 'right' sort of wool - in the right places at the right time.
Full story:
China is now the largest producer of wool in the world (it was fairly recent that it overtook Australia), and Australia the second-largest, and the largest exporter. New Zealand is the third largest producer. In February 2020 the global wool market closed abruptly. It is still somewhat in 'catch-up' mode - wool being a natural product produced on a yearly cycle (and most wool has an almost unbelievably-long supply chain, unfortunately) so it is hardly surprising that there is a 'shortage' ...
Additionally, different types of wool are produced in different places (according to their suitablity for different breeds of sheep) so while there may be - for example - loads of high-quality low-micron Australian merino available so that soft knitwear and fine suiting can be made, it may also be that there is much less available in the long-staple lustre wools from the UK & New Zealand, so that fine carpets can
not be made.
Although much of the early wealth of England was 'built on wool' - and we all know of the 'woolsack' in the Houses of Parliament - most of the sheep in the UK nowadays are raised for meat; wool is a mere by-product and even, in some cases, an unwanted expense. For welfare reasons, sheep need to be shorn - which doesn't come free or even cheap - and then there's the further expense of sorting, packing and transport to the wool auctions. Shearing is a welfare essential, but if the rest of the expenses - the costs of packing, sorting and sending fleeces to market - don't result in a profit, what's the point? Best to burn, compost or otherwise dispose of low-value fleeces. It's not as bad now as it was a few years ago, when fleeces were worth less than nothing, but February 2020 saw the global wool market closed for a significant period and farmers and wool merchants had no choice but to 'dispose of' their fleeces if they couldn't store them or process them.
There is also a shortage of facilities for wool processing in this country, so if anyone wants to (for instance) produce a hard-wearing pure-breed wool from their own flock, and sell the resulting yarn to knitters and/or weavers - or even set up a knitting or weaving workshop in a repurposed barn (diversity in farming of course) they will come up against huge barriers, expense and time in their quest to have the wool scoured and spun to useful commercial standards. There is, though, increasing interest in 'mini-mills' especially in remoter areas.
This webpage - about the mini-mill in use on North Ronaldsay - gives an idea of the processing procedure. And this is without giving any thought to dyeing, bleaching, texturising etc etc all of which require further processing. BTW I can highly recommend the North Ronaldsay wool - it was the wool, in roving form, with which I learnt to spin. Lots of different colours, all natural! And amazingly soft for a primitive breed, the mini-mill does a superb job of dehairing.
People with speciality and/or rare breed pure-bred flocks can make a bit of pocket-money by selling fleeces or parts of fleeces, direct to the handcrafting and hobby-spinner market, but not much. After all, how many fleeces can a hobby spinner use?
I was given a full fleece several years ago by a farmer in the village where I used to live; it won a first prize at a prestigious sheep and wool show but for all that he couldn't get rid of it for actual money! I am still finding bits of that fleece packed away in odd corners; I knitted him a beanie and a pair of wellie socks from some of it that I'd spun - but he wasn't even expecting that - he simply didn't want to have to burn or compost it, which was the alternative.
So, there's no shortage, per se, of wool - but there may well be a shortage of a particular
type of wool. And sock wool has always been a bit of a speciality yarn, especially when used domestically or in a small-scale production facility.
As I suggested earlier, the best way to get genuine woollen socks, is to learn to knit. It's not difficult, it's good for you and is something that has long been done by people such as shepherds, mariners and lighthouse keepers.
