A single test bench doesn't do it for real world usage over weeks of keeping a whole bunch of stuff on the desktop. There's not a single individual whom I know, that has been doing tech support for a few years and familiar with fixing folks slow machines that are going to keep stuff on their own desktop and for good reason. We've all seen what happens. Particularly for those with low VRAM in their machines. It is just a bad practice - period.
Keeping 3 or 4 items in the Desktop folder likely will not cause an issue and am sure most all of us do it from time to time. There is no reason, however, for any of us experienced in attempting to assist others to not provide "best practices" during any troubleshooting attempts. And "best practice" among the vast majority of tech support, you don't keep a bunch of stuff on the desktop if you want to keep your machine running as fast as it is capable.
And yes, I've read on forums all over the place there is nothing wrong with it and it does nothing because they're just files stored in the Desktop folder, etc., etc... That's not what I've seen from experience and as long as I am making recommendations, not storing a bunch of stuff on the dekstop is mine also.