How so ? It takes minutes to install it.
Just download it, copy it and set JAVA_HOME to make it easier for other applications.
I've done this on hundreds of servers during my lifetime and never once had an issue.
Oh, look, there's already an antique jre installed on my os, not compatible with the particular jre needed by this application, which I first need to uninstall. And then hope that it doesn't break anything else in the process, because I haven't been following the minutae of java development environments for the last n+1 years...
I think it falls solidly in the "easy if you know it, and a wasted q hours if you don't" category.
That's two steps. The first one can ruin your day.