I work on alternative data in the hedge fund industry. We're not quants -- we don't try to predict the stock market... instead, we try to forecast how individual companies are performing using aggregated clickstream, point-of-sale, and payments data. It's a data cleaning, timeseries, and modeling problem with a lot of domain knowledge necessary.
LLMs can be helpful (Ie. for example, entity resolution for data cleaning) but the core models you have to use to actually make the predictions (this looks a lot more like "old" tabular data approaches).