When Bernie has an incredibly solid voting record lgbt issues, started a gay pride parade in his town (which they loved him for, I think I read a letter from an lgbt member of the community that talked about how great it was for progress), and has voiced support for LGBT people over the last few decades even when it wasn't popular which by proxy will open more people up to accepting lgbt people, it seems absurd in my mind to say he isn't an advocate just because of how much focus he put's on economics, especially when Hilary (someone who I've always believed has a strong record on lgbt rights besides marriage equality which is why I don't harp on it like other Bernie supporters do) has a history of doing what's politically expedient and "practical" even if it throws things under the bus.
Isn't that supposed to be one of her appeals?
Of course i'm not LGBT so I don't have a full picture of what being an "advocate" entails, but from the outside looking in it seems that both of these imperfect candidates has a strong record on it and that it would be insulting to say he isn't an advocate for lgbt rights, i'd at least imagine someone would say not as good of an advocate rather than not an advocate at all.
And on racial issues Bernie is stronger than Clinton from my perspective as a black man (something I don't believe gives me much credibility, just clarifying because of the perspective some people take towards Bernie supporters).
He didn't call us predators to be brought to a heel, take money from the private prison industry, or in my opinion support general bad policies that hurt all Americans which means minorities got the worst of it while Bernie has been on the right side of 99% of it since he was in college, he also supports Marijuana decriminalization which she keeps tip toeing around and I believe she doesn't stress the role of economics/campaign finance reform in race nearly enough.
One comment on reparations being divisive (which I believe is true), won't change that for me, especially when it would be literally suicide to support it and would probably cause more problems in the long run.
I'm sure you could find a better issue that he backed down on to attack his credibility as an advocate rather than that.
Of course this is just my opinion.
I'm more than happy to engage on this with you, and to see if I can clarify my opinions on the situation as I feel it pertains to me.
I have never knocked Bernie's record on LGBT issues. His votes have been "right." Where I, and others, have issue is mischaracterizing his votes. He voted against DOMA because he said it was a state's right issue, not because he was in favor of marriage equality. There is a difference there, and to pretend that one position equates the other is just not accurate. Bernie was for civil unions until 2006. His voting record is absolutely fine. Therefore, there is no need to make it out to be something that it wasn't. FYI, Hillary was the first First Lady to ever march in a pride parade, and she's said she wants to be the first President to do so as well.
However, I have not seen specific policies that have been put forward by Bernie in his 30 year career that would indicate he is willing to proactively take up issues that are important to my community. I can look at Hillary's time at State, for example, and point out several ways she advocated for LGBT issues. There is a reason groups like HRC support her over Bernie, and it's not because we're all corporate shrills.
Several of the other issues you bring up are important to me as well, and I respect that we approach them from a different angle. As a CIS-white male, I simply do not have the same references a person of color has on specific issues. To that same end, it may be more difficult for a hetero-normative person to understand the way in which I perceive certain issues that affect my community. To me, Hillary has shown a better understanding of the ways in which sexism and homophobia are intertwined. (I actually believe that most homophobia is, in fact, sexism, but that's another argument all together.) She has shown, through policy positions and even simple remarks on things like trans violence, that she truly gets it. I do not get that same vibe from Bernie. He has not proven to me that he actually understands intersectionality at all, let alone how it would impact a trans woman of color, for instance.
And, again, feeling that Bernie Sanders is not the best choice is not attacking his credibility. He would be fine on LGBT issues, I'm sure. I think Hillary would be better. Of course, I'm not a single issue voter, and LGBT issues is just a part of my overall rationale for who I elect to support.