SEOs will always first recommend server-side rendering. But making the switch from client-side to server-side is cumbersome and time-consuming.
But server-side rendering is getting more and more traction thanks to React and its built-in server-side hydration feature. You can even use a prerendering solution like Preact. It has its own CLI that allows you to compile all pre-selected routes so you can store a fully populated HTML file on a static server. This lets you deliver a super-fast experience to the user, thanks to the Preact/React hydration function, without the need for Node.js.