That was my thought, too. It's effectively the same powertrain as the non-hybrid, but with the addition of a small motor + clutch. The rest is just control of the motor.
Super helpful video. I do wish they set it up for a bit better mileage, but it's a pretty nice system and I like that it can operate purely mechanical if anything goes wrong with the hybrid system.
I expect you'll be able to use the inverter with engine off, but keep in mind it's not a huge battery. If you're drawing 20A, it will drain the battery in 45 mins max (probably less because there is probably battery protection to prevent complete discharge) at which point the engine would have...
At least for the Canadian market, the gas model OR is available with a 6' bed, but only with manual trans and no options. Not sure what the hybrid packages will be.
Definitely seems like a bad dealership, but maybe call the front desk and see if there's a different sales guy more knowledgeable on the new Tacomas? When my wife was dealing on a car recently, we switched sales people and had a much better experience even though it was the same dealership.
If the Sport would work for you, the manual comes with the Sport+ options including JBL and towing. Good luck at your dealer! If you find any additional info while there, lmk and I'll update the post.