alt Hacker NewsIn this particular case, it seems like the attackers were trying for plausible deniability (making it look like an accident with an anchor). A comprehensive series of "accidents" wouldn't fit that goal.
(And if they decide they don't care about plausible deniability, they could use sub-deployed timed mines to take out every cable at once.)
Even if these "accidents" are a state sponsored (or at least condoned) action, it seems certain states have realized they can happen over and over again without consequences[0].
The frustrating part of this kind of petty tactic is that bullies can do just enough to annoy and inconvenience their targets, while never quite doing enough to make it worth expending the political capital to hold them to account. From the bully's perspective there's no downside. And if legitimate accidents or rogue actions get portrayed as deliberate then all the better - that just reinforces the bully's reputation as an actor to be feared while further eroding trust in the international institutions that may one day challenge it.
[0] https://www.taiwannews.com.tw/news/5677668