I've heard quants are not as popular as before, due to regulations etc, there's less things to do in terms of maths and algorithms. I wonder if it's true?
The kind of jobs a quant would do has changed a lot since the crisis. I wouldn’t say there is more or less demand for quants, just that there is demand for them to do different things. For example,
Certain derivatives and structured products are less popular than they were before the crisis. For example, exotic equity or fixed income derivatives see much lower trading volume and hence less demand for quants to work out how to price and hedge them.
Credit products are more straightforward now, and less popular. CDOs got a bad reputation after 2008.
Funding costs, liquidity, collateral and counterparty risk are taken seriously now, so linear desks have more to do (building funding curves for different currencies and different grades of collateral) and XVA desks (comprising credit, funding and liquidity valuation adjustments) have grown.
New regulations on bank capital mean more work for quants, both to ensure that regulations are complied with, and to optimise the bank’s capital structure for the new regulations.
Electronic trading has grown, and quants are required not just for their traditional role (models for pricing off-market derivatives like swaps, options and forwards) but also for the roles that would traditionally have been done by human traders (inventory management, pricing, hedging decisions).
Quant hedge funds have grown, and even discretionary hedge funds often hire quant teams to analyse the large amounts of data being produced by sell-side brokers and alternative data providers.
In general I think that it is harder to walk out of a PhD in math or physics with no experience, no knowledge of finance and no programming ability, and get a job as a quant. But that’s not because quants have become less popular or less in demand - it’s because the supply of good quality candidates has increased, and employers increasingly expect applicants to have finance knowledge already, and to be able to write good quality code from day one.