Yes, it's safe when acquired through the App Store or the site you linked to. The only difference between them is you pay to download the app via the App Store, and it's free on their own site.
I use it to run Windows XP on an M4 Pro mini. Even though XP is Intel only, it's also a very small (disk space footprint) and old OS. I actually runs pretty fast even with the Intel CPU emulation.
If you're thinking of running an Intel version of Windows 11 in UTM, don't. Deathly slow doesn't even begin to describe how Win 11 for Intel runs in UTM.
If Win 11 is your goal, download the free ARM version of VMware and run Win 11 ARM within that. With both VMware and the guest OS being ARM native, it runs at nearly normal speed. Win 11 ARM can run most Intel apps without issue.