Well, funny you should mention that. There is absolutely pretty prejudice (in favor of desirable traits), causing measurable economic effects. This seems to include an income boost for blonde women on average: https://www.businessinsider.com/if-you-have-any-of-these-20-physical-features-your-pay-check-will-probably-be-higher-2011-2

And, oddly, CEOs tend to be disproportionately blonde, the thought being that this is a necessary adaptation to avoid being seen as too confrontational (which, for a woman, is bad, because sexism): https://www.inc.com/minda-zetlin/why-women-who-want-to-be-leaders-should-dye-their-hair-blonde-according-to-scien.html

And women are underrepresented at high leadership levels in most places, in part because they are treated negatively if they don't conform to stereotypes, but the stereotypes are not a good match to the perceived demands of many types of leadership position.

So I wouldn't be so confident that there aren't significant impacts--maybe not as significant as race, but still significant--on the basis of hair color. And I wouldn't be so sure that blonde jokes have no power in maintaining gender inequalities.

("The pretty, desirable women are blondes! The others are too bitchy and pushy. And blondes are so dumb, ha ha ha!"--surely you can see how insidious this is?)

Though this doesn't happen with blond hair in most places, if you happen to grow up with red hair in a place where "gingers" are teased, there can be weightier problems. You can find plenty of accounts about bullying (https://www.bbc.com/news/uk-northern-ireland-28872927) and lack of self esteem (https://www.theweek.co.uk/news/uk-news/955393/gingerism-last-socially-acceptable-form-of-bullying), leading in some cases to long-lasting psychological problems, that are of similar character to those suffered by children bullied on the basis of race.

People can be pretty awful to each other, not just on the basis of race. It matters. I wouldn't diminish it.

And this makes me wonder why you're so eager to promote this definition of racism. (Actually, there's a cynical answer that is very obvious: you have had your race-activist tribal identity challenged, and you are engaging in a display of tribe orthodoxy by using a contested definition in the way expected by the tribe. Obviously I can' t tell if this is true in your case, but it's exactly what one would expect looking from 30,000 feet--identity challenge met by identity signaling. If this were true, then I should shut up, because it might be important for you to successfully navigate this tribe-identity challenge, and I wouldn't want to mess it up for you. But you claim you're fine, so I'll provisionally assume that you're fine.)

There are, it is true, quite a number of people who use "racism" to mean "racial prejudice backed by power". There are also quite a number of people who colloquially use it to mean just "significant racial prejudice".

The funny thing is that you're explaining one position without in any way arguing for it. This is what you do when a topic is completely settled. Is it? Can you link to something definitive? I mean, I can explain the difference between "fog" and "a cloud", even though I think the definition is a bit batty, because meteorologists have decided to carefully parameterize the distinction: https://eartheclipse.com/geography/difference-between-fog-and-clouds.html.

Maybe there's a good reason to use "racism" this way, but could you please share?

For instance, you say you are fine, and you didn't need the group membership for anything important. But what about someone else in a different place in their career--maybe someone younger, white, who has decided to make a career of activism, and for whom inclusion in this group actually would make a substantial impact on their career? Is it then racism?

If still no, how big does the impact have to be? What about someone who is white but at a school where whites are in the minority by far, and who is bullied extensively? There's power and prejudice...is that racism?

Conversely, suppose a black person applies to 20 jobs and hears back from 3 of 20 and would have heard back from 5 of 20 if they'd been white...but the extra two jobs were the worst fit anyway (likely, because these effects tend to be stronger at the margins). So, actually, no impact: they get the best job for them anyway, and even were saved a little time by not having to consider two less-ideal jobs. Is this not racism? (But would have been if one of the two missing callbacks would have been the best job?)

I don't think your definition as stated really comports with any customary usage of the word "racism", because you added individual there.

The broad definition is something like: racism is strong racial prejudice, that is, a strong negative attitude or strong beliefs about the poor qualities of a particular racial group.

And the narrow definition is something like: racism is racial prejudice from the dominant racial group who has or who historically had the large majority of ultimate power in a country, directed against non-dominant racial groups. (Sometimes people lean heavily enough on the historical part such that it is definitionally impossible for anyone who isn't white to be racist, not just in the U.S. but in the whole world.)

If there's an explanation for how this intermediate individually-aware power-based definition of racism can work without constantly getting mired in unknowable details, can you please share it?