As much as Scott Nietlich(?) deserves the ridicule he gets, he does makes valid points at times.Others mentioned the poor leadership at Hasbro and problems with Disney, but on the economic front it’s a few different things.
China was at one point known for being an extremely cheap place to manufacture products, but as they became an economic powerhouse wages for Chinese workers began to rise.
The price of oil has also risen since then, making plastic more expensive to produce and is probably a major reason why we no longer get things like ornate display bases or giant BAFs.
And of course, good ole fashioned inflation.
Many of these changes were starting to become apparent even in the final year or two of ToyBiz. You started seeing more body reuse not just across Legends, but also the sister lines like Spider-Man and X-Men Classics.
One video he did a while ago talked about the economics of Marvel Legends and he pointed out that the price freeze/fear that Hasbro had has also lead to the current quality levels. His take was that ML figures were basically frozen at $20, then $22, etc. for longer than they should have been because Hasbro didn't want to risk market share/sales. So to offset the frozen prices they started nickel and dime-ing the production side. Accessories, parts count, paint apps all started to be cut back to keep the target margins without raising the retail price.
He pointed out things like lack of paint on "metal" parts which lead to the swirly plastic on gold and silver metal parts of figures. Where only a couple years previous those parts would have been painted. So we kept getting less, and eventually what happened? They still raised prices and we still got the crappier production products.
In the end we are probably in the end stage of the action figure hobby. Not to say it will completely disappear, but it will become even more niche as prices continue to soar. Kids are already ageing out earlier and earlier, but pricing is speeding that phenomenon along.