My A/C is 10kw running, with 18kw tankless water heater. You oversize generators when drawing lots of current from switch mode power supplies as harmonics confu

My A/C is 10kw running, with 18kw tankless water heater. You oversize generators when drawing lots of current from switch mode power supplies as harmonics confuse the AVR. Aka tankless water heater. I have a home lab, full rack. Around 4kw including a dedicated A/C. I have excess power and will run an extension cord to neighbors if needed. I’d also want capacity to charge an EV should I get one. Price between 22kw and 40kw was negligible relative to total project cost. The only downside is I have to turn on everything in the house twice a year to exercise it and avoid wet stacking. Final note is that in order to use an automatic transfer switch you must have sufficient capacity for connected loads. A smaller generator would have forced me to install a second sub panel for loads I want to run during an emergency.