Half of it's misspelled and it's bad form to spout words incorrectly. Yes s/he is saying "cool, cute thank you Machigerita" which is not bad, but s/he said in the way of a typical weaboo, which /is/ or can be bad. A better way would have been to say This is cool! So cute! Thank you Machigerita! Mainly I think it's because it's in all Caps. Why am I elaborating? This happens on too many videos to count and this was the first i seen of someone questioning why.
If Fraisiere and Granita were a symbolized of Luka and Miku, I think they should switch face 'cuz that'll fit a lot better -although...the way they are is already cute-