I work in the industry, and the "evidence" gathered on the impact of HFT in the markets is nebulous, at best.
It's certainly a fair and reasonable way to participate in the markets the way they're currently structured, particularly in the U.S.
There is a lot of hand-wringing right now about the retail investor leaving the equities markets, and some evidence that it's happening. It's often blamed on the volatility of the markets, and fingers pointed at HFT. I haven't seen any real proof that there is a correlation here. We do know that the markets are fragile right now - liquidity is shallow and fragmented across multiple venues, retail investors continue to make net withdrawals from equities, and unexplained mini-flash-crashes occur and correct themselves multiple times daily. It's not clear to anyone how much HFT has to do with any of this (either positively or negatively).
IMHO, both the problems I've cited and HFT itself are a consequence of the market structure and changing technology. It's not clear to me if the regulators or government will take action to correct the fragile markets, or what impact that would have on the HFT business. As an example, the European parliament today unanimously voted, as part of MiFID II, to require that orders be held for 500 milliseconds, a HUGE difference for HF traders.
If it is a job you're interested in, I'd say go for it, and that it's a morally neutral position to take. Be aware that regulatory changes may add significant uncertainty to your chosen field.
