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Mostly, I'm interested in folk's opinion why all this changed, and why now is the old way of handling magic badwrongfun?
First you'd have to tell us where you got the idea the old way was badwrongfun.
I think handling magic significantly differently than non-magic isn't a good idea for several reasons, ranging from fairness to plausibility.
From there... in the real world, lives don't go according to plan. People go to school, learn work related skills and knowledge things, but only some folks manage to end up doing exactly what they trained to do in school. In the real world, people change careers, trades, and focus pretty frequently.
Now, in my fictional world, maybe it doesn't make much sense for a character to pick up advanced magical abilities without having shown previous predilection for them. Maybe that stretches some people's suspension of disbelief. But, on the other hand, having a character only be able to respond to influences in his world through herculean effort, or not at all, often leads to a less satisfying fiction. Pick your poison.