At one stage long ago, there were a few quants, often working as individuals attached to a single business unit.
Traders rarely, if ever had even the most basic quant skills, many did not even have a degree of any kind, let alone a PhD in maths or physics. A small number had MBAs but that was more often coincidence than a requirement to do the job.
Risk was mostly run by accountants who not only had no understanding of derivatives, but based their credit limits on conversations at golf clubs. That's not an exaggeration, and it was still happening more recently than you might think. The head of fund management at one well known asset manager has a degree in English. And yes, before you ask, their performance has not exactly been stellar.
Now it is very difficult to start a career in trading, fund management or risk without at least core quant skills, and many roles in software development, operations will test you on quant skills before they let you start.
Some areas that you might think of as wholly non-quant now have significant penetration like sales and even the accountancy functions. Although relationships are a key driver in sales, the best margin products have also been the most complex, and there has been a growth in the sophistication of advisers who help the buy side make less terrible decisions. This means some sales staff have more than a shallow understanding of their products.
In the current climate, quant techniques are now required in some parts of compliance, which to me is the signal that all parts of finance have finally become within the reach of quant career.
This is of course a positive view. Of course I am not saying when overall finance employment will hit the current level agaqin, but I am clear that for quants the decline will be less sharp because of the greater % of jobs that will require your skills.
Of course these positions will have a very different mix of types of work than the classic Derman quant, and will require a wider mix of skills. This will be difficult for some of you, and more than a little disappointing. The sharp divide between quant and non-quant job will continue to erode, which will mean greater flexibility in the sort of work you can do, but at the price that you may end up doing more work that you neither enjoy nor excel at.