I'm only new to the Zorin OS community, less than 24 hours, andt I have to say my experience so far with the advice being offered is genuinely refreshing and amazing. This post is a perfect illustration of that.
Ironically, it is about the only one I feel able to offer a contribution. For me, there are 2 key issues to keep in mind when comparing performance differences between OS's and apps:
1. How much RAM does you have in your PC?
2. Do you have a mechanical Hard Drive or an SSD?
Budget and old PC's typically only have 4gb of RAM at best and / or use old mechanical Hard Disk Drives (HDD). My rule of thumb (especially for Windows) is to double the minimum amount of RAM specified.
So, if you only 4gb of RAM, you are likely to be better off trying Zorin OS Core (2gb min) or Lite (512kb) than Windows 10 (4gb min) due to their respective memory usage.
In a similar fashion, if you only have a HDD, but also have USB 3.0 ports, using a portable USB 3.0 SSD as your boot drive is likely to give better performance than the old HDD. (Although getting a SSD installed internal is obviously even better!)