Well Finale is not a browser and I can tell you Finale 27.3 scrolls just fine on my Win 11 computer. So I would look for a issue with your machine.

In Studio Mode, Finale does indeed redraw at about 1 FPS on while scrolling on Windows 11.  It scrolls fine on macOS.  Tested on 4 different PCs here, and an M1 Pro MBP.  Studio Mode is the worst offender, but with a lot of information on the display other modes also perform less than what you'd expect.

As the display raster increases, the performance decreases, so you will see better performance on a 1080p display than QHD, and better on QHD than UHD.

It has to do with how the application redraws the display.  It seems to be CPU bound on Windows, and this tends to be laggy on modern machines.  Maybe threading is not optimal?

Samplitude Pro X has [had] the same issue.  MAGIX worked around it by hiding different elements as you zoom out, so you don't bottleneck when redrawing - otherwise, you got the same laggy scrolling issue that Finale exhibits.

Probably not a viable solution for any type of DTP application, though :-(

OP can buy a new PC and it won't change anything, unless the CPU performance increases and breaks through a point where it can handle the redraws that Finale is throwing at it... or if he's using a HiDPI display, perhaps he can try running at a lower resolution and seeing if that may alleviate the issue.

His PC is not the problem, though.  It's an easily reproducible problem, in that it's just the normal state of application for the software.

Thanks for the detailed answer！