Yeah, assuming someone build right next to you at best, also assuming that you had placed a beacon as close to the side as possible and keeping it in your area which is five spaces in with a radius of 50 and a distance of 2 chunks (32 blocks straight) you can affect 13 of their blocks in the chunk hence why you can't get any boosts because you would give them regeneration protection jump or speed without them wanting a boost from a beacon. Also why beacons are cheaper.