Like the OP I've been pulling all types of trailers for decades and only one came with a sway bar which I used since it was there although it was a 31' Airstream that really did not need it.
When I can see the rigs of those that say you have to have sway control (from previous posts too) I can see why... the tail is going to wag the dog. If you have a long wheel base TV that is not maxed out and plenty of tongue weight you do not new sway control. If your TV is marginal then you need all the help you can get but it's really just a band aid.
I've seen too many pictures of wrecked TT trailers that had some type of sway control still on the tongue. If you used that big storage area behind the axles for heavy item it's going to take you to the scene of the accident regardless of sway control or not.
