Well, cameras are part of the sensor array mostly, and assist with navigation. Speakers can be useful if the vacuum is stuck or low battery away from its dock.
I remember seeing that vid around when it came out and it just furthering my notion that we really really do live in a world where basically everything nowadays is designed shittily, or outright with intentional obedience, all to keep us buying shit that breaks down or wears out, instead of even having the option to save a bit more, learn how to maintain a well designed thing made with quality and save tons of money and resources in the long run.
Edit: damn it, I just wrote up a review of the T20 before seeing it was already posted. The T20 I got (used, obviously) from the original owner on ebay in 2013 is still going strong 75 years later!