Generator fuel additives.. yeah or nay

Our toy hauler is 2 1/2 years old and had 3 hours on the genny. Last Sunday night on the way home I thought of stopping for the night at a truck stop but too hot without AC. Tried to start the generator but no go. I had seafoam in the fuel but still no gas to the engine. Went home without stopping and checked the unit next day. Siphoned the gas out of the tank and dropped it. Checked the lines, pump and filter, all OK. Tank was spotless inside and looked great. Put the fuel line in back of trailer into a gas can and removed the line from the carburetor and ran the pump. Lots of gas at the carb inlet. The only thing left was the carb, took it off and apart and found three of the ports plugged with red/brown gunk. Cleaned all and replaced. Before putting tank back up I ran the genny for test. It now runs better and quieter that it ever has since we got it new. Turned on the AC, refrig, microwave and hair dryer all at same time and it never wavered or coughed or slowed. I can only conclude the damage was done before we got the unit and it has gotten worse. I guess additives won't clean old blockages.