I broadly agree, but to further add some color: if you like nature, what you have easy access to in DC is methadone compared to the Bay area, or really anywhere in the western US. Shenandoah National Park is... nice; the Chesapeake Bay is... nice. Further afield, Western Virginia has some pretty bits, and you're not too far from the beautiful areas of Appalachia, the South, or New England. But you're not that close either, and you certainly won't find any Yosemite. Unless outdoorsy activities are a very important part of your overall wellbeing, this probably shouldn't overrule other factors, as ultimately there are nice things around to see and do (be glad you at least have methadone!), but for some people it is in fact a clear and somewhat painful tradeoff that you will be reminded of acutely every time you go visit friends in the Bay area.

I would add that another factor in DC's favor is diversity. Of course, DC is one of the most international cities in the world, and certainly the country, in large part due to its importance to international affairs, so you will easily hear 5-6 languages spoken in a day out on the town. This is not necessarily all that different from the Bay area, though I think DC's international connections are in fact significantly more diverse due to the range of countries from which people often come to DC. In my experience, the social and professional circles of most EAs in DC are also significantly more demographically diverse than the Bay area. Personally, although I am white, I prefer living in a place where I feel like people of any race or ethnicity would feel comfortable, which is often not how the Bay area feels to me; DC seems significantly better on this dimension. If you are Black in particular, the Black community which makes up a plurality of DC's population could be a strong positive factor for you. On the other hand, it's worth noting that DC has a much smaller Asian population than the Bay area, so if those communities are important to you, this could be a downside (for example, there are very few Buddhist temples in DC).

I agree with a lot of what other people have said here. I think the key message I would emphasize is that 1) yes, the EA community should do a better job at inclusion of this kind of diversity (among others), but 2) you really just shouldn't even think too much about "intelligence" in finding your path within EA, bc there is almost certainly SOME way you can make a significant contribution given your unique conditions. To the extent you're concerned about "intelligence" being a limiting factor, I think this should also incline you to chose topics and types of work that are intrinsically interesting to you. If it's interesting to you, you'll naturally engage with the topic intellectually while working in the area (even if your role is peripheral to the intellectual work). Over months and years, the cumulative effect of continual, immersive engagement can be much greater than you would expect when thinking "will I be able to learn X?" before starting out.

I'll add my own experience, which I think is similar, in case it feels reassuring to you also: I went to a good-but-not-great large public university in the United States where I studied humanities, and worked for the first few years of my career in not-particularly-impressive organizations before finding EA. I was rejected from career coaching by 80k (I think both bc they were relatively capacity constrained at the time & bc I didn't have any obviously impressive line-items on my CV), but was still very interested in the cause area that I'd chosen. I was never really worried about "intelligence" as a limiting factor on my overall impact per se, but I was definitely not sure I'd be able to master the technical aspects of the area, which did influence my expectations for what kind of roles would be a good fit for me.
Because I found the topic interesting though, I kept reading up and eventually got into a junior, operations-type role in a prestigious, relevant organization. I think I got this role actually not at all due to my self-study of the topic, but partly bc the unimpressive, non-impactful thing I was doing at the time was kind of similar to  the role I was hired for, and partly bc the hiring manager mis-perceived it as being more impressive/prestigious than it actually was. I think this was basically random luck.
In any case, at this organization I found that while the very smartest people indeed seemed much smarter than me, the people in roles that might imply they were much smarter than me were actually not clearly all smarter than me (or even had fundamental skills/aptitudes that I did not), they had just learned different things, which I could also learn, and many of which I did learn through continuing to do self-study (again, I found it intrinsically interesting besides being potentially important/impactful), asking colleagues questions, and just absorbing stuff over time. 
Since working at this organization, my career in the field has basically gone smoothly, including having opportunities to move into (what people generally perceive as) "smart person" roles or to advance along my previous path. At some point, 80k even basically told me that they probably made a mistake in not offering me career coaching, I think bc they had heard through the grapevine that I was generally adapting well to the environment. My impression is that even if I had been much less capable of understanding the technical aspects of the area, there would have been no lack of opportunities for me to have an impactful career in the space.