I think it used to be harder to host than it is now. I think the only thing that might be hard now is sifting through all the tools for hosting and the analysis paralysis that can come with that. Heroku can get pricey at scale, but heroku and others are options that make it dead simple. Then there are a ton of options for how you might want to self-host. There are plenty of guides for getting docker setup with it, opensource heroku-like alternatives (most using docker under the hood), and plenty of resources (maybe too much).