I'm pretty sure it's fine to make threads about his tweets since he seems legit and accurate.
He also follows up:
Frankly Nintendo struck a goldmine timing the release with the SDCC announcements yesterday. It may not have been able to time it with Endgame's theatrical release, but this may be the 2nd best possible thing it could've been timed with.
Hope this encourages Team Ninja and company to really dig into the game and try to fix all the performance issues it has.