So what is the catch here? subtle advertisement? it's pretty obvious, everyone will say no to the question... -- assuming I interpreted the question right since it's poorly constructed.
In any case, they do appear to be shady as pointed out above.
It is not the first platform that I have noticed. Some platforms do this, whether they are paid directly or through referral links or a third party.
This approach is clear from beginners, so I do not advise anyone to trust any positive reviews, especially from beginners. Look for negative reviews and try to make sure they are accurate.
Bitget exchange spammer is a good example
Pretty much every platform with no budget for actual promotion is doing it in a backdoor way like in bitcointalk spamming their platform name on multiple threads so they can create a buzz and the same goes through social media where you can see someone claims "Ohh, hey I am using this platform which is very good and trusted blah blah, so as you said don't trust the blatant one-word positive reviews like "Excellent", "Very Good" which is an obvious sign of farming positive reviews.
My Input is don't try risking your own money on any new thing, give it some time and you will know if it's legit then start using it.