That's what happens when something doesn't work properly ie is broken, it doesn't do what it should. Hydraulic or not. The ram could be distorted, the pipes kinked, fluidways bunged up, washers rotten, fluid contaminated with air/water.
You can't say "that's not the problem because it's hydraulic.........", it's like saying "they can't be corrupt, they're the police". But you did say "SHOULD not be stiff", and that's the key.
And I did say that hydraulic is no feedback.
And you can have friction settings on a hydraulic system. Only that they are at the engine end or wheel end and usually not directly incorporated into the hydraulic system, although these exist as well.