[Loughla]

I'm almost certain that delivery of filament requires some kind of supply chain.

Also, last year, I wasn't able to get filament for about 3 months due to the pandemic.

[belval]

I don't think the parent's point was that filament didn't have a supply chain, more that filament's supply chain was mostly undisturbed during the pandemic.

At no point was it hard to buy a 1KG spool of PLA as far as I know.