In a since-deleted post on her site Pottermore, the writer argued that while freeing the slaves was noble in isolation, being enslaved is what’s better for the elves right now and they should stay that way until they politely ask to not be enslaved.

https://archive.md/2020.05.08-221547/https://www.wizardingworld.com/features/to-spew-or-not-to-spew-hermione-granger-and-the-pitfalls-of-activism

I don’t know who the original writer is and I don’t know of an archived copy before Pottermore ended and everything was transferred to Wizarding World, but I believe it’s from an era of Pottermore where she wrote the blog entries herself