Because
a- TRT haber is nothing but government propaganda and not trustworthy
b- No one who has been paying attention to Turkish defence industry takes MSB Arge seriously, especially in a subject like a jet engine because they have zero experience in the field, and questionable experience in other areas
c- They also claimed that they produced all of the parts themselves, which is bullshit of the highest order because required expertise and technology to build those parts only exist in TEI.
d- Erdoğan, who loves talking about defence projects, who loves putting his signature on defence projects, who loves posing with defence projects, didn't even talk about them, or go near them at all, let alone signing them.
So, there. There is nothing to talk about except for how their bullshit cast a shadow over otherwise great expo.