If your flight is scheduled on a 737 Max 9, be proactive. Look into rebooking on a flight using a different aircraft. It’s very unlikely they will be back flying any time soon.
You need to learn your opinion is not fact. E+ is NOT an upgrade and it is not UA’s policy to move people into E+ because they ask. Of course, some agents don’t follow the rules. E+ certainly does not have unlimited leg room.