Is it monolithic or using micro-services?
Yes in the past, not quite now.
The major differences are the size of the system, the number of users is serving and the size of development team.
We got very small teams on projects, and our applications doesn’t really need to be web scale, so we are just using a monolithic approach, albeit modular.
I have always worked either by myself or in a small team. And microservices are needed for large teams with at least 9 developers, otherwise the microservice will do more harm than good.