There are real downsides to running my website on VPS I sysadmin myself & a homegrown pile of code in JavaScript, Python, Swift, and Zsh. The code is all over the place in every sense of the phrase.
But I can personally guarantee that it'll keep working and remain available so long as I can afford the DNS and VPS fees. I can't say that about any other place I post on the internet.
Own your own space on the web. Post there. Write there. Link to it from your various accounts elsewhere. #indieweb