Hey this thread is along my alley. I'm Asian, and I love traveling alone and have done that in the past in several occasions - I have many good and bad experiences, of course.
IMO, it's very true that majority of the world assume that Asians don't speak any English, we all speak 'Asian language'. I've been asked before, randomly, to translate some conversations in Korean, Vietnamese, and Japanese into English. Ha.
As the result, other travelers typically ignore a solo Asian traveler until s/he opens her/his mouth and mutter something in English.
During my last solo trip to Hong Kong and Macao, I had several conversations with locals regarding my background. True that I'm Chinese decent who appears to be a Chinese, but since I grew up in the 1960s-2000s Indonesia where Chinese culture and languages were banned, I can't speak any Mandarin. As a result, I received several insults as a non-Chinese-speaker Chinese, who abandons his culture 😞
My observation: majority of Asian solo travelers, if any, usually gravitate towards other Asians too. Of course I'm talking about those who live in a strong Asian cultures (ie Asians who don't really exposed to many other races). This is not a racist thing, just a comfort level as naturally exist inside any person's mind.
Since I'm an Indonesian who lives in the States, majority of my traveling friends, if any, are Americans (uhm, it is true that Indonesians typically don't travel that much around the world, they're touristing around the world!). But that doesn't mean that I only stick with Americans, I usually open to other travelers whom I met along the way.