What is the modern way to design (and maintain) things?
The problem with UML was it was far too specific. The aim was to just about generate the whole program code using charts which isn't what anyone needed.
Are those supposed to be thrown out after first or second release?
> The aim was to just about generate the whole program code using charts
That wasn't the aim of UML.
Any model (including UML) serves two main purposes: to create system design and to document that design.