You can create shared libraries to increase reuse and sharing of

features among teams. But there are some downsides to it.

Since shared libraries are implemented in same language, it

constrains you from using multiple types of technologies.

It does not help you with scaling the parts of system that need better

performance.

Deployment of shared libraries is same as deployment of Monolith

application, so it comes with same deployment issues.

Shared libraries introduce shared code that can increase coupling in

software.

https://cselectricalandelectronics.com/question/what-are-the-disadvantages-of-using-shared-libraries-approach-to-decompose-a-monolith-application/