Gareth Edwards predicts that the recent transfer of sovereignty over the Chagos Islands from the UK to Mauritius will lead to the demise of the .io domain: https://every.to/p/the-disappearance-of-an-internet-domain, via https://www.metafilter.com/205826/Itll-be-a-sad-day-for-crypto-bros
Since my blog is hosted by github.io I am somewhat concerned about this possibility, but the MF commenters seem to feel it is unlikely.
Relatedly, from a link in the comments: five past removals of two-letter country-code top-level domains: https://domainincite.com/30406-five-times-icann-deleted-a-cctld-and-what-it-means-for-io (they were .yu, .tp, .zr, .an, and .um). A relevant quote: "The fact that ICANN hasn’t acted to remove .su from the root, thirty years after the Soviet Union collapsed, could be seen as precedent."
@11011110 And here we don't even mention the other (strong) possibility : the potential and future overflood of Chagos islands (in my opinion the "why" UK move there asses on the retrocession)
@11011110 Those articles pretty much cover the topic. You can find a lot of takes out there but I suppose the default way to guess is that the URL of your blog will change but there will be years before that happens.
@soaproot The question is which comes first, the demise of .io, the demise of github pages, or the demise of my blog. No reason to rush to do anything about one of these things when another will get me.