Classic Mode FPS drop while in combat

Just started a new campaign and wanted to play in Classic Mode rather than Reforged since I prefer the older art style.

However any time I engage in combat that is more than just a few units, the FPS suddenly drops to only a few frames per second and even freezes the game entirely for a few seconds at a time. I have tried running fullscreen, windowed, fullscreen windowed, vsync on and off and nothing has helped. Running in Reforged does not have this issue at all and only happens in Classic Mode.

General specs:

Windows 11 Pro

AMD Ryzen 9 3900XT

32.0 GB DDR4

RTX 3060 Ti

Any help would be appreciated!

Considering how Blizzard is increasing the game’s requirements, Classic Mode will soon be abandoned—players will be forced to play with the new graphics. Take a screenshot of my prediction, gentlemen.

are you saying they will soon be forced to use reforged mode only?

No, that will never happen. Don’t worry.