With a high-end 4070Ti and 32GB RAM, Firefox should run flawlessly. Since Edge performs well, the lag is likely due to a corrupted Firefox profile or Hardware Acceleration conflicts. To fix this, go to Settings > Performance and toggle Hardware Accel...
I assume this has something to do with this change.I had to manually re-add Startpage, which might already be a big hurdle for non-technically inclined people.Therefore I suggest looking into this, as this might, in fact, reduce the usage of Startpag...