I imagine, being an art form, there is almost limitless possibility for complexity and difficulty in dance. However, I would argue the same is also true for strength sports, which ultimately are a type of martial art. I don’t think one is categorically simpler than the other- they both offer people of any skill and ability level lifelong challenges. My point was not to claim dance was easy but that “exercise” is not always something simple and mindless that once learned you just tune out and let your body do. Personally, I can’t stick with something boring- having ADHD, exercise is only possible for me if it is also fully mentally engaging.
I'd argue dance has a higher skill floor but both have a high skill ceiling.
With dance you need minimum 4 limb coordination (its more than this) to get started. You need rhythm and you need to memorize choreo.
At low weights lifting is pretty straightforward even for Olympic lifts. But your form only gets found out as you increase load and there's high risk of injury, and as you say you need a high focus.
As someone said - you chose the exception to the rule and the average person needs to use exercise machines because they lack the body awareness to even attempt strength sports.
That said the technical timing to strength sports is different to rhythm in dance/music. They both take focus but I think the brain is engaged differently. Especially as lifting is usually one movement and the movement is performed in a short burst. Whereas dance is a long sequence and usually a very different energy profile which is important. I do a lot of stuff but I recommend dance to people (as someone who doesn't really dance myself) because it forces you to relax in a way a lot of other exercise forms don't
