The debates of microservices vs monorepo never really end, with articles arguing over one side or another. I came across this article against microservices the other day, and while it has some very valid points and yes, if you're starting a new company or a new project and say "I know! I'll use microservices as backend for this", it's probably the wrong call; I'd probably argue that at a certain point in the growth of an organization, microservices begin to make sense.
While thinking about that, that got me thinking -- that kind of statement is really not unlike the argument for React vs not-react (the framework-less option usually being jQuery with some static HTML) in frontend.
If you're starting a hobby project and you just want to build an MVP, using React is probably overkill, unless you're working on a highly interactive web app (dashboards, charts, etc.). For most web sites with some minimal set of interactivities, static HTML and jQuery is probably sufficient.
The difference between the React vs jQuery question in frontend and the Microservices vs Monorepo question in backend is probably the point on the spectrum at which it makes sense to switch. For frontend, once you get a certain size of a frontend web app (that isn't even very big), it probably starts to make sense to start using a framework already (although for myself, I'd definitely prefer Svelte over React). For backend, you can go a looooong way on a monorepo setup before moving to microservices. Many legit tech startups still run fully monorepo and that's completely valid.