Claude Code cache is not 1 hour. There is a "Closed as not planned" issue in GitHub that confirms that it has been moved to 5 minutes since March: https://github.com/anthropics/claude-code/issues/46829.
I started seeing the massive degradation exactly on the 23rd of March, hence after a few days I unsubscribed because it was completely unusable, with a ~5h session being depleted in as little as 15-20 mins.