When it comes to the sub-bending forms is it more of a “its so hard only a few can do it” or something intrinsically only some can and some cant do no matter how hard they try?
Rewatching Korra and I am wondering if Bolins inability to bend metal is more of something that he’s unsuitable, id assume the “attitude” (hard to say but like the same blockage aang had with his difficulty to earthbend stemming from his airbender way of thinking).
Considering Toph and Suyin seem to believe they could make anyone learn to metal bend seems its something all earthbenders can do but is extremely difficult.
Makes me wonder if metalbending and lava bending are mutually exclusive as the “attitude” needed to bend one or the other is so anti-thetical to earthbending and because of that someone like toph who is like the earthbendiest earth bender wouldnt be able to do it.
Metalbending would than be like the earthbender attitude turned up to a 1000, as you would need the hubris to bend literal metal.