I can think of two benefits off the top of my head.
1. Subversion "tags" don't work for me. I think this is because I have deleted files since the last tag, I posted a message here, nobody was able to help. So I don't always do it when I should. Only a small thing, but one that annoys me. Actually I find the whole idea of tags in subversion very clumsy to use in any meaningful way.
2. Sometimes I make repeated mistakes when building a package; under subversion I have to make a new commit for each one before testing. Under git, I can test it with a local commit, and amend the commit if required before pushing it.
3. With git it is rather obvious when there is a new upstream branch (git fetch will tell you). With subversion, it is easy to miss, I think it requires manual checking. Recently, I have duplicated efforts to support Python3 in a package because I didn't notice it was committed in another branch.
Oh, wait, that was three. So sorry.
Also, sometimes I find subversion can be very slow when it needs to access the remote server.
I am sure there are more reasons, these are the ones that have annoyed me recently. Unlike some, I am happy to continue using subversion. However I feel I could do a better, more professional job with git.