Experian was fairly difficult to do, and required I prove things in a pretty non-trivial way. It involved sending a fax, which was annoying, but not exactly horrible.
Equifax, the company that got hacked, let me unfreeze it discouragingly easily. They asked me some questions on the phone that I figure were likely available in the leaked data, with only one or two questions needing a little more access.
The two questions that needed more access were frightening to me, though. They asked me to confirm an up-to-the-minute balance on either my bank accounts or the cost of a few things I purchased very recently (I forget which it was). Either way, why do they have that data? Why does the company that got hacked have that? I certainly never gave them permissions to have it, and I would like to revoke their permission to have this information.