Do RGB mousepads interfere with wireless mice?

No, the LEDs won’t mess with your 2.4 GHz signal. The RGB lighting runs on low-voltage DC power with simple PWM circuits that don’t generate interference at 2.4 GHz. If you’re getting dropouts, it’s almost always distance, USB port placement, or a bad dongle. The only edge case is a cheap no-name mousepad with a poorly shielded USB pass-through hub, but that’s a cable problem, not the LEDs.