You can complain about things like(taken from the linked letter):
*universal free public college
*cancelling student loan debt
*restore the right to vote for all formerly and currently incarcerated people
*Medicare for All and universal childcare
*demolished homes
*boycotting for political reasons
*cap credit card interest rates
*guarantee a job to everyone who needs one
*increasing of defense spending
Those are all legitimate issues to be worried about. And issues that if they bother you enough are reasons to not vote for Buttigieg.
But they are not LGBTQ issues, and framing them like that makes it seem like every LGBTQ person has to be on the side of the people who wrote that letter and completely silences LGBTQ people who might be more moderate or even conservative.
These are LGBTQ issues, though.
Someone who gets disowned and tossed out on the street by their parents after coming out of the closet needs economic security.
Someone discovering they're trans later in life leading to a divorce needs economic security.
Someone incarcerated under discriminatory laws deserves their vote restored after those laws are removed.
Boycotting businesses with discriminatory labor practices or that support discriminatory organizations who directly harm people is an LGBTQ issue.
Economic hardship prevents people from taking care of themselves. It locks people into bad situations that they need to escape. It makes it too dangerous to risk openly being who they are. These are universal issues, but they effect vulnerable people in a way that the general population doesn't experience. They prevent LGBTQ people from being able to exercise their rights to be who they are. They prevent people from escaping abusive households. Etc.
Shame on me for failing to explain this, but yes. It was something I was struggling with all day.
Look- any one part of L,G,B,or Q and T and + can perhaps enjoy a relatively nice time. For example, Christianity doesn't have anything against Lesbians. So should Lesbians stand with us?
Bisexuals (like me) can deal. Should they stand with us?
Gays have strong energy. I, for one, welcome them into our coalition.
We are all queer. We have formed a coalition.
...And that coalition must address the fundamental issues which affect the vast majority of us.
Yes, there are gays who are now valid citizens, who are allowed to marry.
They didn't really need to marry.
Yes, Lesbians are also allowed to marry.
The Bible doesn't say they are abominations.
People unite together under a coalition. You might argue it's wrong, to come together in such a way, but it's definitely natural. And this coalition includes all minorities. Ethnic included.
I stand with all my friends. Queer, minority, or dispatriated.
Edit: Just because the main issues have been addressed doesn't mean that we have to abandon the disenfranchised groups which helped us along.