Heads are round but a beard can have corners. If you think this passage means that the Earth is flat and square, you also have to make the case that human heads are square. Good luck with that.
Extremity, extreme part, corner: כַּנְפ֥וֹת – kanaph
To cease, fail, have and end: אַפְסֵי – ephes
If my feet are at the end of my legs, then the coast is at the end of the land. The ends of the earth is simply where the land stops: it ceases, fails, has and end. The beach.
The Farthest Parts of the Earth
Depending on what English translation you're reading you may see this rendered as "the coasts of the earth," "the sides of the earth" or "the ends of the earth."
The Ends of the Earth
If the Earth has ends does that mean it has to be flat? No, because "end" is a translation of a word which means "extremity or furthest reaches of" in which case we're talking about the beach.
Brachiopods
Brachiopods aren't an evolutionary dead-end which got wiped out in a mass extinction. Well, there was a mass extinction, but it didn't wipe out the Brachiopods. Many were buried in Noah's flood but many alive today.
Scorpions and Millipedes, first Air-breathing Animals
The first air-breathing animals to appear in the stratigraphic column were the ones who just happened to be living on the beach or at the coast during Noah's flood.
First Vascular Plants in mid-Silurian
The first vascular plants that were buried in Noah's flood are on top of the beach sand which is full of dead scorpions because they were growing in the dunes inland of the beach.
Low-lying Continents with Some Epicontinental Flooding
"Low lying continents with some epicontinental flooding". That's how you describe a world-wide flood without saying the words "world-wide flood."