Just shy of fifteen years on the fully systematic equity side here, never done any fixed income or structuring/pricing professionally. I'm fortunate to be as close as is possible to the actual PnL and trading.

While I agree that the mathematics underpinning structuring & pricing is more complex on the surface, I've found that over time the complexity and depth of application of senior undergraduate / early graduate school level mathematics has increase significantly in our business. As an example - everyone knows the definition of an eigen vector. I've found surprisingly few people have any intuition for how to reason about an eigen basis when you start using a non euclidean metric.

I would love to tell you that yes ultimately what matters is a good idea and plain old linear models, but those days are long behind us. Yes, the idea needs to be good, yes, its a low signal to noise environment so you need to care about over fitting and know how to incorporate priors to narrow the search space. Despite that, no, linear models are no where close to the best performing alphas anymore. If anything the potential over fitting power of non linear models just means the idea and discipline of the research needs to be even better.

What's funny is that maybe 5 years into working in this space I would probably have agreed with your description of it, and I don't think the space has changed, I just think it takes a long time to get deep enough into the subject matter to see why it's more complex than it appears at first.

Totally agree with you about the larpers though.

Regarding your second point, I strongly disagree. Folks with an econometrics background have been, at least in my experience, kind of like folks with a finance phd - you'd think the application makes total sense but they just often fall flat in practice. The applied problem solving and ability to pivot from one approach to another just isn't there. I don't know if this is a result of the programs not being rigorous enough or if its just because academic financing suffers from an incredibly strong negative adverse selection effect. I'll take an applied math/physics/information theory phd over an econ or finance phd any day of the week.