>Especially with the landscape now, asking a likely non-technical user to download, install and launch software is a lot to ask and will impact your conversions if you're not an established product.
With the landscape now, installing and launching software involves clicking on it in the app store and waiting a few seconds for the installer to finish.
With the previous landscape, installing and launching software involved, for Windows, downloading an installer, double clicking on it, maybe going through some default settings, and waiting for installer to finish. For Linux, instead of downloading an installer, you pull it with a package manager, maybe go through some default settings, and maybe wait for the installer to finish.
It was never that complicated unless you were compiling all of your software from source, but that's an extreme fringe minority in the whole universe of software consumers.
The process of "installation" in the SAAS model is merely replaced with registration. Instead of downloading the program, you're uploading your credentials. The complexity is still there, because it has to be, but it was never that difficult for the end user to begin with. And the process of registering for a site is, arguably, more complicated than native software in many cases. I don't have to deal with individual passwords for each of my native apps, for instance.