Not necessarily.
Electronic earmuffs will do one or more of the following for you:
1. amplify ambient sound so you can hear weak noises, or conduct normal conversation in a noisy place,
2. allow connection to external audio devices such as radio, CD or cassette players via optional cables,
3. allow two way communication if optional accessories are attached properly,
4. allow listening to AM and/or FM radio in certain models.
However, the ability to attenuate sound still depends on the NRR value and not what it can do with the electronic circuit. For instance, the Ultimate 10 ( model H10A, NRR=29dB ) will offer better hearing protection than a Tactical Surround ( NRR=25dB ).