The Jones family can definitely be categorized as personal selling. They have used several techniques through out the movie such as conversation and demonstration, like on the golf course where Steve shows off the new design of the clubs and gains sales through the staff recommendation rather than directly.
The main point that the Jones family gave off with their selling techniques was that this next product would make you better or happier somehow. This is very similar to a lot of popular brands now, ie the tracksuit everyone buys because of how attractive and confident Kate looks in hers. One could even say reference selling in which the members of the family themselves are the happy customers with positive results from a product, one such example could be the earrings that Steve shows Larry saying he intends to gift them to his “wife” Kate.
I wouldn’t consider their selling techniques ethical as they weren’t genuine in their reality. Even with social media posts, the viewer is aware that there is editing and other tools used to perfect the image being posted. In the movie, people are losing what they have to achieve something that isn’t even real. A lot of the time people lose sight of the fact that the reality isn’t necessarily what they are being shown. But at the end of the day being unethical doesn’t mean something is illegal; it is a value question and the answer can vary from person to person.
I would like to be friends with someone happy and confident who shared tips but if I were to find out that they were actually trying to sell me something; I wouldn’t feel comfortable as there would be an immediate doubt as to whether they are genuine or not.