The devs have made it clear that even though there's a lot of opposition, it's a core design tenant that you can't really respec your builds.
A lot of players have brought up the issue that, there's are countless possible builds per class, and countless variations to each build (imagine even just 100 possible builds, and 10 variations for each build... that's 1000 respecs!). Being able to try them all would be a lot of fun, but the devs insist that having 30 Mage characters on your home screen if you want to have 30 builds is what they want as a design decision.
Even if the OP farms gold for many hours, it doesn't really matter because in the end it'll be too expensive to realistically try out all the possible builds or to switch up your build when you get bored with it.
It's sort of a sad realization which is why I was being a bit facetious because it's sort of a sad realization.