Hello-
Sorry to hear about the choppy scrolling. It’s possible that this might be due to lazy loading images.
Lazy loading improves your website’s loading speed by deferring loading your images until your user is just about to scroll to them. Here’s a video explaining how lazy loading works:
Other than W3 Total Cache, you may be getting lazy-loading from plugins like JetPack, Hummingbird, or another performance plugin. This feature is also included in WordPress natively since 5.4. Keep in mind that lazy-loading is actually good for your site speed and SEO, but it could cause the issue you’re describing.
You might be able to reduce the impact of lazy loading by optimizing your images. I hope this helps!