Good journalists cite their factual claims, even/especially if they're believable.

I've never heard of underwater landslides, and I don't think it's a reasonable assumption that a reader knows anything about them.

> I've never heard of underwater landslides

They are a huge cause of tsunamis, with the slips often precipitated by earthquakes.

In geology, there's a literature about cable breaks caused by "turbidity currents".

In particular, this 1952 paper by Heezen and Ewing is celebrated https://gwern.net/doc/technology/1952-heezen.pdf

> I've never heard of underwater landslides

Good heavens. You do surprise me. There have been some vast ones, e.g.

https://en.wikipedia.org/wiki/Storegga_Slide

Some have the potential to massively affect human life well above sea level, e.g. La Palma in the Canary Islands, which when it goes will inundate much of the east coast of the USA:

https://www.e-education.psu.edu/earth107/node/1609

The video from that is sensationalist but makes some good points:

https://www.youtube.com/watch?v=6utAunBKXV4

Facts are sometimes just facts, not impressive fun facts.

>It doesn't seem unlikely to me.

It's not unlikely, it's probably true.

But it's at least a little coincidental that it happened during a coup in Niger.