Comment by rramadass

It is the complete modeling language (class diagram is just one artifact) that people are looking at using with Formal Methods along with regular Software Engineering. For example Sequence Diagrams are extremely useful in understanding the dynamic nature of a System. Lots of papers have been published, IEEE workshops and there is even an attempt at integrating the B Method with UML to give a UML-B variant. Like any language it is up to the developer to study it and learn to use it productively in his work. Of course it is not the "in thing" but quite useful nonetheless when used appropriately.

Automatic Formal Model Generation from UML Diagrams – An Implementation Experience - https://ieeexplore.ieee.org/document/9753518

UML-B: Formal modelling and design aided by UML - pdf at https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&d...