Do I really need a special jersey for e-bike riding, or can I just use a regular cycling jersey?

You can absolutely use a regular cycling jersey on an e-bike, but e-bike-specific jerseys offer real advantages. The relaxed fit is more comfortable in the upright e-bike position, the extra pockets accommodate the additional items e-bike riders carry, and the enhanced reflective elements address the unique safety concerns of higher-speed assisted riding. If you already own road jerseys that fit comfortably, they'll work — but if you're buying new, an e-bike jersey will better match how you actually ride.