Welcome, Richard! Your experience sounds unusual; perhaps your lab "pushed' the development a bit. In my experience, a 1-stop push mainly boosts the highlight densities, and is mainly useful it putting some pep in negs shot under very low-contrast light.
It's also true that underexposing C-41 films raises contrast, and giving it a generous exposure moderates the contrast... and also gives a smoother look especially in the shadows, and richer shadow tonality.
For a 400 ISO C-41 process film, either color or the chromogenic B&W, I just set my light meter to EI 250, and in doing this for 20 years I've been very pleased at the outcome.
As Peter mentioned, the chromogenic B&W films tend toward low contrast, and your lab machine prints should look somewhat on the dull side usually, unless it was in very contrasty light. But this low contrast is actually a benefit, recording a very wide range of tones. In the darkroom or in digital scanning, the contrast can be boosted in the print or scan, and in doing this you can choose what data is discarded.
