I returned to STO during Season 6, and experienced this bug all season long. Existing reports have received the reply I've come to expect from Cryptic. This bug is still affecting every STF that I play during Season 7, so while I don't hold alot of hope - I figured it was worth a post. Forum friends, thanks for reading.
Put simply, if I die during a space STF, I would say that there is at least a 50/50 chance that upon respawn, the arrow keys which direct my flight will cease to do so.
In an effort to troubleshoot this problem, I have during Season 6 installed on screen display software to verify that the input from my devices was being received by the computer. All the other keys on my mouse, keyboard, and gamepad continue to get responses from STO.
All of my gaming equipment is in top condition by top brands (Logitech, Razer, etc). My computer, likewise, is in good condition and well maintained. I'm a more hardcore gamer than most & experience no similar problems with any other games or software. Perhaps embarrassingly so, but I'm the kind of nerd that if I did have a problem with my gaming equipment I will either fix it ASAP or drive out to Fry's at any hour of the day to get an immediate replacement. I can quite confidently certify that this issue is not caused by anything on my end.
There is no indication that a few keys on multiple devices have any intermittent hardware or software errors that cause them to disable only when respawning from space STF death. I have not experienced this problem on ground missions.
Usually, I can jiggle this handle by swapping to firefox and loading a web page. When I return to STO, this has a chance - but not 100% - of returning the arrow keys to their normal working state.
TL;DR? Space Death makes STO stop responding to arrow keys. Pleez Fix.