I wouldn't say that subversion is dead or that git is better (actually, it's the opposite). It might be true, however, that git is the more suitable option in many situations, for example the most common use-case is OpenSource code management with many features, which are developed in parallel, and many collaborators. But that's because git was specifically designed for that purpose.
For smaller projects or corporate projects, in situations where everyone has agreed to certain standards and the project itself is not in the same situation as Linux, SVN might make a lot more sense, because it has a lot less complexity. Heck, even Microsoft's TFS might be a better option than git or SVN in some cases!
Git needs a lot more knowledge and extra commands. In fact, there are so many, that I doubt even git users of many many years know them all well enough to confidently make use of them. It's nice to have features, but if you just want to have code management and simple branching, git is an overkill.
Also with growing numbers, git's complexity also grows. Keeping all the small and fractured repositories in sync is no easy feat! Every single developer has to keep track of changes and patches. Especially when used in a purely decentralized environment, missing patches can happen easily which leads to lots of problems and errors.
The next problem with git is when you have repositories which weight several hundred GBs. The Linux kernel alone is 2GB in size, but there are larger projects (GNOME, to name one) and having to copy over the repository to your computer means sacrificing space, traffic, time and performance. Btw, big repositories are not bad! They actually have a number of advantages, like visibility, atomic large-scale refactorings, better dependency management and collaboration across teams. Companies, like Facebook and Google have such big repositories. They might be more than a terabyte in size. Try to manage that with git o_O
Another problem is authentication. While git either allows a user to read or write everything, you can have permissions on a per-directory base with SVN.
Git has problems with binary. SNV supports special lock-modes for binary (unmergable) data, so if you have a project with lots of assets, git should not be your first choice!
Further reading: