One way to prove you can really keep up with the cool kids is to move your blog to GitHub the day after they get bought by Microsoft.
I’m not actually worried by that: one of the key features of a git repository is that it doesn’t have the only copy of any of your stuff. The main motivation for switching was to use blogdown rather than Tumblr, because my blog is mostly text.
Converting from Tumblr was a bit of a pain, partly because the Python setup on my desktop machine is a mess, partly because there’s a lot of MathJax in the blog, and partly because I wanted to fix up the font choices in some posts. I ended up doing a lot of it by hand. It wasn’t too bad, though.