Hi @Anonymous,
In my personal experience thus far, most programs will run a bit faster in Win 10 than Win 7, and the main reason for this as far as I know is that Win 10 uses less resources from your computer than Win 7 does for running the Operating System.
I think Win 10 uses like 100MB - 150MB of RAM less than Win 7 to run the OS
So on a PC with limited RAM for example the difference is easier visible than on a high spec PC, but still, its not a major difference.
Most people will just upgrade to Win 10 because of the extra features it has that Win 7 does not have.
(Ps. Last thing, Win 7 has proven itself to be a very stable OS, Win 8 on the other hand was disappointing to say the least as there was a lot of compatibility issue's with some programs like Inventor, but Win 10 is once again nice and stable like Win 7 is - Just my personal opinion )
Hope this helps
☺