An infusion of algae into the Nile River, or fallout from the Santorini eruption would indeed be imperfect but okay explanations for the Ten Plagues of Egypt -- if the Ten Plagues of Egypt had really happened.
But they didn't. The overwhelming scholarly consensus is that they are literary devices in a origin myth.
It may surprise you to know (I didn't think it would, but given the notes on this post, maybe it will after all) that there is significant academic debate as to whether the Exodus tradition has any historical merit at all.
Israel Finkelstein, former director of the Sonia and Marco Nadler Institute of Archaeology at Tel Aviv University, and one of the most prominent historians of the ancient Levant, wrote: "There was no mass Exodus from Egypt. There was no violent conquest of Canaan. Most of the people who formed early Israel were local people—the same people whom we see in the highlands throughout the Bronze and Iron Ages." (p 118. The Bible Unearthed)
Others have taken a slightly more agnostic stance, and engaged with the Exodus as an exercise in memory-making, like Nadav Na'aman does in his excellent article, "The Exodus Story: Between Historical Memory and Historiographical Composition". There he comes to the conclusion that the Exodus story is a cultural memory of Egypt's departure from Canaan, not the escape of the Israelites as related in the Pentateuch.
There are dozens more peer-reviewed articles on the historicity of the Exodus that I could link you to now. Hundreds that I don't have on hand. There's even been significant scientific pushback on the natural cause theory of the Ten Plagues, with physicist and theologian Mark Harris, University of Edinburgh’s Lecturer on Science and Religion, taking the whole idea out to the woodshed in his article "How did Moses part the Red Sea? Science as salvation in the Exodus tradition".
(It's also worth nothing that Siro Trevisanato, the microbiologist who put forth the Minoan Explosion hypothesis in The Plagues of Egypt: Archaeology, History and Science Look at the Bible, refers to skeptics of Biblical historicity as "Bible deniers" in his book. Not disqualifying, but illuminating.)
I'm not using this post to Take A Stance on whether there is a kernel of truth to a folk memory that an ancient group of people used to formulate their identity. That's an ongoing scholarly conversation! But I am using the historicity debate to underline the fact that we don't even know if the framing device AROUND the plagues is true.
Every single person on this website has access to way too many scholarly resources for us to post with wide eyes about how literal miracles from the Bible have been proven. Particularly when even the "sources" cited in the post (The Independent and Time Magazine, respectively) make certain to point out that the timeline of the Exodus is debatable to say the least, and might disqualify the Santorini eruption entirely.
I don't know guys, I think we're better than just blithely throwing euhemerism at religion and calling it a day.