I used to be a market maker of stock options, amongst other things.
> It doesn't take 30 mins after the news breaks for stocks to move
When it comes to markets, test every assumption. In reality, information diffusion is unpredictable and heterogenous [1]. This is due to, in part, the "effects of limited attention in at least part of the population of investors in the market, interacting with some more sophisticated investors with better access to information processing technologies" [2].
> The derivative markets are almost exclusively dominated by hedge funds, banks, large investors
Individual stock (versus index) options are actively traded by individual investors [3]. Individual investors also actively trade futures [4].
[1] http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.652...
[2] https://pdfs.semanticscholar.org/b180/3e674cc6be4de275cda1aa...
[3] https://pubsonline.informs.org/doi/abs/10.1287/mnsc.2013.184...
[4] https://www.sciencedirect.com/science/article/pii/S156601411...