I think that article is maybe BS? there was a story a while back about the US running low on manpads or something and production couldn't keep up, when it was just old stock that the US weren't using, and it was only being made in the first place to fulfil low priority orders to other countries. A lot of bread and butter stuff being sent to Ukraine is just tat that nobody in the EU wants, just like Russia has massive stocks of 50 year old T-62's that are long obsolete https://www.popularmechanics.com/military/weapons/a40232488/russia-throws-half-century-old-tanks-into-ukraine-invasion/