I still feel like you're underselling the article however.
Is obviously ultimately parallelism, but parallelism is hard at scale - because things often don't scale - and incorrect parallelism can even make things slower. And it's not always obvious why something gets slower by parallelism.
As a dumb example, if you have a fictional HDD with one disk and one head, you have two straightforward options to optimize performance:
Make sure only one file is read at the same time (otherwise the disk will keep seeking back and forth)
Make sure the file is persisted in a way that you're only accessing one sector, never entering the situation in which it would seek back and forth.
Ofc, that can be dumped down to "parallelism", because this is inherently a question about how to parallelize... But it's also ignoring that that's what is being elaborated on: ways s3 used to enable parallelism
I still feel like you're underselling the article however.
Is obviously ultimately parallelism, but parallelism is hard at scale - because things often don't scale - and incorrect parallelism can even make things slower. And it's not always obvious why something gets slower by parallelism.
As a dumb example, if you have a fictional HDD with one disk and one head, you have two straightforward options to optimize performance:
Make sure only one file is read at the same time (otherwise the disk will keep seeking back and forth)
Make sure the file is persisted in a way that you're only accessing one sector, never entering the situation in which it would seek back and forth.
Ofc, that can be dumped down to "parallelism", because this is inherently a question about how to parallelize... But it's also ignoring that that's what is being elaborated on: ways s3 used to enable parallelism