The interesting thing is that your line of advice really just needs a single, model minority person to prove it right. "Look! She didn't accede to the haters! Please ignore all the other people like her who gave up along the way! She obviously focused on what was under her personal control, and that's all that mattered."
But it isn't all that matters. If that were true, diversity in tech would not be an issue. Instead, only the most resilient people, those most willing to overlook the ongoing and systemic discrimination, make it.
Furthermore the REASON why I pointed out that it is a spectrum is that it isn't all or nothing. If you're truly stuck feeling like a victim a lot of the time and can't change it, you're still better off than you would be otherwise. Better off does not mean well off - discrimination is real. It just means better.
But that isn't a reason to deny people help, deny people the chance to say "hey, look I'm feeling really alone right now". I wouldn't be as "tough" as I am now if it weren't for a few people who gave me a hand when I truly needed it. I wouldn't be where I am without reading a ton of blogposts by other marginalized people who feel the same way as I did.
There are, no doubt, people who like to wallow in their insecurities, but they aren't any worse than the people who say the marginalized should just suck it up and work harder, or that people who feel marginalized should shut up.
The phrase, "To the extent that you can..." was meant to convey the fact that the perfect ideal is not feasible. I also tried to make it clear that the attempt is worthwhile because even if your best is only an occasional success, you'll still wind up better off than you would otherwise.
On the question of toxic organizations, I'd like to point out that recognizing that the organization is toxic and choosing to be elsewhere was under your control. I commend you for making that choice. There will always be toxic people and toxic organizations. Some, like the police, we have little choice about dealing with. But there is no need to put up with ones that we can avoid. And by avoiding them, we make our lives better.
However experience suggests that you are likely to wind up around people who are quick to explain all failures as discrimination. Because they do this for themselves, they are unlikely to be successful. If you adopt this attitude, your odds of success are also hurt.
However, I believe you can’t possibly extend that (positive and helpful) feeling to an outside “political” statement. If our aim is to make the industry welcoming and accepting to everyone, I believe we should do more than what you describe and try to figure out a way to make it right.
It might not help minorities in tech right now, but it will eventually.
If you have a minority that has every disadvantage but believes that they CAN succeed by their own effort, that minority will succeed and it will reduce bigotry against them. Indeed the history of the USA supports this - we have had wave after wave of disadvantaged immigrants. They have nothing, have trouble with the language, and are widely discriminated against. But a generation or two later you have seen Italians, Koreans, Chinese, Vietnamese, Russian Jews, Afghans, and many other minorities integrate into the mainstream and do well.
But get a victim culture established in a minority, and things won't improve for them. They are unlikely to actually face more discrimination than, say, Cambodians did when they arrived here penniless and not speaking the language about 40 years ago. But they will have a worse future.
Look at it a different way. If you're from a disadvantaged minority, you've likely got a strike against you for having a bad background, and another for current discrimination. Add a victim mentality, and you're out. It doesn't matter how good the evidence is that you're an actual victim, it is the mentality that you can't afford.
Maybe those things can't be changed in the short run, but maybe speaking up about them helps move society in the direction of changing them in the long run.
To the extent that you can focus on what is under your personal control, you are likely to be happier and more productive. To the extent that you focus on things that are not under your control and can't be changed, you will be unhappy, unproductive, and will have a built-in excuse for your failures. This is not an either-or choice, it is a spectrum. And the farther you manage to go towards taking responsibility for your life, generally the better you will do.
This does not diminish the real challenges that various historically disadvantaged groups have. It is what I believe the best advice is for them based on everything that I have learned..including from people I respect who are members of various disadvantaged groups.