I am irked by Review SPAM, that is, reviews which are posted to promote a product and not to critique it. Review SPAM dilutes the value of reviews and costs me time and effort to sort out the wheat from the chaff. There is probably a market (at Amazon and elsewhere) for a product that flags Review SPAM for removal.
The content looks like it's machine generated. Check out how the speaker reviews are all the same in the summary.
Who cares? He identifies that he was given the product for free in all these reviews.
True, but he identifies up front that he was supplied a free item for review, so he's not breaking any laws. As for Amazon's ToS, who knows - I'm too lazy to check right now.
The other top 50 reviewers (on a few randomly-clicked items) are doing the same thing, but put the advisory about being supplied with a free item at the end of the review. These reviews come off as being little more than descriptions of the product, some mild inoffensive personal opinion, and a 5-star rating unless something is very wrong with the product.
Annoying, but what else can one expect? If there's a reward out there for being in an exclusive category, some people will try to game it, and in the case of Amazon the reward appears to be that people will send you free stuff. Lots and lots of free stuff, which I presume you can make some money by selling or trading away.