Purplecanadian08Honestly i do both but in my experience bmx is harder to learn but easier to master in the other hand skateboarding is easier to learn but harder to master.
Simpler answer skateboarding is alot harder.
take the fact that chimpanzees already view humans as wizards because we spend all our time balancing on 2 feet, the fact that some people can guide a skateboard onto and down a 10 stair handrail is just insanity.
bmx has a wide footprint where you can use both your arms and legs for balance and leverage. Its not as easy physiologically as skiing but its way easier than skateboarding.
You can make up for having bad balance on a bmx bc you can use muscle strength to muscle through undialed landings like you can on skis, but if you arent dialed balance wise on a skateboard you arent going to land it.