It was a major assumption coming from Shuttle Loop's changes. Since Meta Knight cannot go into a glide from the move anymore, it's a safe assumption that he, like Pit, has lost the ability to glide, denying him one of his many recovery methods.
So it's not confirmed. We don't go with safe assumptions, we go with facts on here only. It's a very important rule here. Same reason we didn't update Luigi's Final Smash till we had cold hard proof, not just a fair assumption from the PotD about it. He didn't actually say it, so we waited for gameplay. He confirmed himself it was a "a move", but that was it. Then a video came up, and voila, we could add it to places. However, unlike that particular move(which was heavily implied by the Pic of the Day itself, like a darkened screen and Luigi glowing, we have zero implications that MK cannot glide anymore).
@
Frostwraith
: As noted, we don't know if MK lost the overall ability to Glide, just solely his Shuttle Loop no longer has it and nothing more. As said, no "safe" assumptions are useful. Just like we can't assume anybody other than Pit cannot glide. Wait and see, and all.