This is an interesting question, but I think it concerns physiology rather than physics. As I'm a physiologist, I'll attempt an answer.
Our color vision begins with the different spectral sensitivities of our cone (photopic/bright light) receptors. These are often called red, green and blue cones, but in fact each is sensitive to an extent to a side range of wavelengths. But this does not account for many color vision phenomena.
Here's what does. The information conveyed by these cones is processed in the brain (including the retina, which embryologically is part of the brain) by what is called an "opponent" mechanism; i.e., this mechanism has three channels, one for luminosity (black/white B-W channel), one for blue or yellow (B-Y channel), and one red or green (R-G channel). Note that the latter two opponent channels in that the signal generated by a single wavelength of light is EITHER red or green, never both, or EITHER blue or yellow, never both.*
Now, if you add wavelenghts (as you did, as each stimulus is a mix of wavelengths) lights, what you see is the sum excitation of each channel. In order to perceive white you need to have a mix of wavelengths that stimulates relatively similarly B, Y, R and G. If you were far enough away that the stimuli were mixed (blurred) or better mixed the lights from each together with lenses I THINK they would look lightish red-blue. I say that because (i) your red stripe has some blue, the green stripe some yellow, and the blue lots of blue, for a B-Y channel B response, for blue; (ii) your red stripe has lots of red, the green stripe has only a little yelow, and the blue strip has some red as well, so the sum is R-G channel is R, red; and (iii) There will be activation of the non-color BW channel by wavelengths lights whose color aspects cancel out, so the light will be bright, or low hue saturation or "lightish."
If you want to understand better, you can see the classic paper on this on line (Hurvich and Jameson, 1957) on line.
See Figures 1&2 for the layout of the channles,and Fig 4 for the responses to lights of single wavelengths. Note that about 480 nm is RG = 0 and BY = B, so perceptually pure blue, 510 nm is BY = 0 and RG = G so pure green, 580 nm is RG= 0, BY = Y so pure yellow, and that no single wavelength is BY = 0 and RG = R, i.e. the is no spectral pure red. Think about that next time you see a rainbow, which is the only time most of us see an approxiamte dispyy of tjhe visible spectrum hat (picture and so are all mixes, not single wavelengths).