Absolutely true. All a chip can do to a n/a Honda is adjust the fuel mapping, raise/lower the redline, and adjust VTEC engagement. That's really about it. The fuel mapping is 90% of that change, but it will be totally minimal on a stock engine.

Chips are really one of the LAST steps on a n/a small-displacement engine. Wait until you have a larger throttle body, larger manifold, cams, valve work, maybe port/polish, etc... then when you're flowing a lot more air, you'll start seeing big gains from a modified ECU. Or if your power band is raised/lowered.

Everyone hears stories of VWs and Audis making huge gains with chips, but for a more or less stock Del Sol, it won't do much at all.