WTF! I am at an HFT firm in Chicago, this is insane. This seems to be a lot like an offer from Radix, or Headland, or maybe Algo Dev at HRT.
I think an interesting target for comparison with big tech is Jane Street, since their culture and WLB are good, so the main QoL drawbacks of finance don't apply. A new grad will get ~300k at Jane Street, though probably not with this large a sign-on.
Jane Street, from what I recall, is 300K (base + bonus) and 125K sign-on, and also it is non-negotiable. No idea what their numbers are like for experienced hires from competitors.