This sounds like the spaceship problem. Whenever you build a spaceship to take people to another planet, it will be passed by a later ship which was built to go faster.
Reminds me of my games of Civilization. Should I spend few more turns to build additional engines to my spaceship, or should I launch it now and risk being overtaken by a faster ship.
In real life its so much more complicated than that. Because choosing to "send ship now" will result in huge amounts of progress in overcoming obstacles you could not have known about until you actual began the project.
It seems like the answer is always send out a test ship as fast as possible, knowing that it will absolutely be overtaken by a ship with more engines AND the knowledge gain from the first ship.
I don't think that's quite right - it's more that they're a lab and not a product manufacturer, so they can't decide to go mass-market.
Even if they decided that they want to go public with a virtual keyboard/mouse/controller and virtual heads-up display that you use by wearing an electrode net, the current team would not be able to make that pivot. End users won't be debugging Labview sketches, spending weeks training a neural network to recognize virtual keystrokes, or shaving spots on their scalp.
Personally, I expect that the V1 product here is approximately just that: a game controller. A few buttons, a pointer, maybe a little haptic feedback. It would be great for me if it supported text input and output faster than a keyboard and terminal, but I don't think that's likely to happen in an early version.
Even less likely is that we're going to jump straight to The Matrix. Valve needs to admit that, and be happy with a limited version, instead of letting it fizzle out in the lab.