The problem with Gatsby is when you make occasional updates to the data, and you want those to be reflected quickly (e.g. if your users update something and want to share the update immediately afterwards). Gatsby builds are slow (over one minute for the most basic of sites) unless you sign up for Gatsby Cloud), and right now it’s impossible to regenerate just one page in production without Gatsby Cloud.

So you have to put up with stale data, or re-read it again like in a regular client-rendered web app.