I typically go the github pages route. I used to buy domains for every project I spun up, but the collective bill started to add up for a bunch of very low traffic sites for projects that didn’t pan out. Now I just use github.io.
The other concern is legacy. I’m getting up there in age. I would like some of my work to continue to be useful after I retire without me paying for domain renewals or worrying about hosting. Without my intervention a github.io site will probably outlast a onionisafruit.com site.