I really do want to do this, precisely because the software in the repo is often out of date, if it is even there at all! I really don't like the idea of a mandatory middleman between the developer and the user.
And since I really do want to do this, and do it often, I can say with quite a bit of certainty that
> It is that simple.
Is complete and utter bullshit! Sometimes you get lucky and the developer produces AppImages or a static binary, sometimes you're less lucky and have to grab the binary and its dependencies and write a startup script that sets LD_LIBRARY_PATH, sometimes you're even less lucky than that and get to use patchelf to force it to use a compatible ld.so, but most of the time you end up having to compile the damn thing from source like it is 1975.