Boy are characterizations like this getting tired. An actually accurate title would read something like: Farm and industry run-off in certain areas of the world is depleting oxygen in certain parts of the ocean. The vast majority of the issue isn't related to rising temps, it would still be there if there were no rising temps. It is the agricultural and industrial runoff in what I suspect are very, very specific part…
I'm not sure why you think we should take your non-expert, evidenceless hot take on a BBC article more seriously than an actual study, but if you'd like to dig in more, here it is: https://portals.iucn.org/library/node/48892