Ummm…this is because many in the media wants Collins to lose and they (and Schumer) think Platner stands in the way.
By contrast, they want Talerico to win, so Paxton beating Cornyn was the desired outcome.
Now that the primary is over Paxton will get plenty of attention.
I’m not saying Graham Platner should or shouldn’t be a candidate for a Senate seat, but I am saying that the media’s treatment of Platner as compared to its treatment of Ken Paxton is the same as the media’s treatment of Joe Biden as compared to its treatment of Donald Trump. The media bolsters the MAGA narrative that there’s never a decent Democrat nor an indecent MAGA Republican.