Nitpicking is silly but that image is bad too.
Yep Daenerys didn't eat or drink anything for over a day. She also knew exactly where Eastwatch was, despite having never been there before, and luckily didn't overshoot or get lost over the Bite where no obvious landmarks existed in open water. I guess she looked at her table a bunch or the sun was always up even though it took over a day.
Maybe her dragons are blessed with a sense of cardinal direction, in addition to being able to fly 90km/h based on "runnig humans" in past episodes.
Moving on.
The average speed of a raven of 80km/h, as per the original Reddit post, is based on the average speed of a homing pigeon, but of distances of 640km, so about a quarter of the distance to Dragonstone, meaning the raven is keeping the same pace on a trip 4x as long. Also it's not resting apparently despite the longest recorded flight being 1800 km.
Umm what else?
Oh yeah Gendry, a smith from a tropical climate, can run for 5-8 hours in freezing alpine conditions he is unused to after a day of hiking and fighting.
Yep, this all works. You couldn't just do some fairy basic things like, have the squad taken ravens with them (you know, like how Mormont taught Jon to do), or have Daenerys wait at the Wall in the first place. Honestly it was a problem you could write around.