Storing data files on desktop OK now?

Apologies in advance for what is probably a stupid question. Until now I had a 2008 iMac with the OS updated through Snow Leopard, and I feel like Rip Van Winkle waking up after a ten-year slumber.

With my old iMac and OS, storing data files on the desktop was discouraged--here's a snippet copied from a 2006 discussion right here on the Apple support communities: "Everything on the Desktop is treated as a window by the Finder. If you have enough things there you can bring the Finder to its knees...the Finder will stop responding while it attempts to cope with all those 'windows.'"

Now I have a 2020 MacBook Pro with OS Catalina, and while reading through Apple's instruction manuals, I'm reading about creating "stacks" of data folders on the desktop--so now we can put data files on the desktop without causing problems with OS operation?

If so, would these data files and folders be stored on my MacBook's internal storage SSD?

If I create data folders on my desktop, they'll appear in the Finder? Where?

Thanks in advance for any help you can give me.