Yes. Here are a couple of quotes and links for reference.
The Fairphone 3+ was launched in August 2020. It has upgraded front and rear cameras, improved audio, an increase in the amount of recycled plastic it contains (40% rather than 9%) and Android 10. The rear camera has a larger sensor, intelligent scene detection and a higher dynamic range. The front camera has a bigger sensor and a higher dynamic range. The new cameras and speaker are alternatively available as modules that can be swapped in the original Fairphone 3.
The audio improvements cannot be achieved purely by a speaker module upgrade. The speaker module is only for the rear/side speaker and output is only improved if the new core module for the FP3+ is used. Fairphone 3 - Wikipedia