Interesting stuff
It's a topic that is prevalent to me because I actually agree with the OP - it's very difficult to claim to be Pro-Black while dating a person of another race. It's always been my understanding that being Pro-Black means being solely for the betterment of black people including having a black family and children (operating under the premise that the nuclear black family is the backbone of the current definition of Pro-Blackness). By proxy, it's pretty difficult to claim to be pro-black then if your wife is White/Asian/Other and your children are bi-racial. Because at that point, your bloodline becomes - for lack of a better term - diluted and your potential legacy would then potentially cease to be black in the advent of your death (for e.g. your mixed children dating non-black people, thus further diluting your once predominantly black bloodline). So in that sense, I cannot disagree with the OP. I think there's nothing wrong with still identifying strongly with your blackness and doing what you can to help your community that you've grown up in, but it's still pretty difficult to claim to be pro-black fully, knowing that your children aren't black.
My mother, for all intents and purposes, is bi-racial. I'd always thought of her as black, as does most people who meet her, but both her parents are half-white - there is also a minor amounts of Amerindian. However, she identifies solely as black, hates white people, and strictly forbids me from dating out and having mixed children - despite the fact that she is technically mixed
. I'm dark like my father, so there's no real debate about my blackness, however, I concede that I am not pro-black as I'm not opposed dating interracially regardless of my mother's wishes so in the event that I possibly date out, I could not claim pro-blackness nor would I attempt to.