I'll toss my hat into the ring as I just finished cleaning up and installing basic software on a new laptop and have the same experience as many others.
Windows 11 Home 10.0.22631
i7-12700h
RTX 4070 mobile (140w)
32GB RAM (DDR4-3200)
Chrome Version 122.0.6261.70 (Official Build) (64-bit)
Edge Version 121.0.2277.128 (Official build) (64-bit)
Having just installed both browsers, I haven't tweaked any settings from default.
Map is 38x28 at 70 px with what I'd describe as medium detail (a dozen tokens on the Token layer, approximately 30 overlapping & layered ground/snow/tree/boulder/footprint/wagon track images on the Map layer. Dynamic Lighting is on and five light sources are on the map.
When displaying this map in Edge, GPU utilization averages ~30% with jumps to ~45% as I move tokens around the screen or scroll across the map. Scrolling and token movement is smooth. When I open a blank tab in Edge (effectively hiding Roll20), GPU drops to ~2%.
In Chrome, GPU utilization immediately jumps to ~75% with spikes to 100% just from displaying the same map (no scrolling or token movement). Moving tokens or scrolling across the map sustains GPU utilization north of 85%. Scrolling and token movement is jerky. When I open a blank tab in Chrome (effectively hiding Roll20), GPU drops to ~2%.
This thread appears promising - https://www.reddit.com/r/Roll20/comments/185hiod/roll20_lag_solved/. I will try it and report back shortly.