For most people I'd say yes it is. Say what you will, but there is a huge amount of discrimination towards visible transgender people. This seems to be especially true for transwomen. If you pass, you are treated as any other young woman. If you don't pass, you are suddenly a freak.
Every time I bring this up, someone gets into a debate of male vs. female privilege, but let me say that being visibly transgender is about worst thing you can do to yourself in terms of career, education and social (dating) opportunities.
If you had a career for 20 years and you're established financially and socially, not passing might be doable. However for a fresh college-grad in her early 20s, passing is paramount. I wouldn't even DARE walk into an interview presenting female unless I wanted to be laughed out of an opportunity. No one wants to hire or admit a transgirl when there are 100s of equally qualified cis-guys and girls applying as well. Not passing pretty much denies you any opportunity at any client-facing careers. So I'm pretty much forced to drudge it out in male mode until I have my surgeries.
I guess this is why I have a hard time relating to the 40- and 50- year olds here who can brush off not passing. It's also why I envy the girls that were able to transition early so much. I know I won't be passable before I have FFS. And in white middle class suburbia, presenting female while I'm unpassable is just about the worst and most humiliating thing I can think of doing. So basically I need to make this massive jump from presenting male to having FFS and presenting female full time just to really kick off my transition.