Yes really there are two markets: eyewear manufacturers (including BluTech, from your link) have started filtering a little bit of light, but usually these wavelengths really don't make a big difference for computer screens. BluTech is unique because you can see the difference, so it does more than most.
Also, there are efforts to make screen covers, or to move the blue primary over a bit or to change screen spectrum by a tiny amount. There you find some self-described "standards" (no consensus standard) for blue-light safety in screens, with a ton of press about it. I like what they are doing for flicker, but the spectral changes cannot make much difference, and so the press around it seems very disingenuous:
Here are some examples:
https://fluxometer.com/rainbow/#!id=filter/BluTech - this one makes a visible change
https://fluxometer.com/rainbow/#!id=filter/ZAGG Visionguard - this one claims to help your eyes without making a visible change
Based on the numbers, changing the brightness of your screen by any amount at all will make a bigger difference than this kind of filter.
