Whilst i do not deny that there are more then likely many racist people staying in hostels i think you might be over thinking this and i hope that you don't let this experience ruin your trip. I say this as someone who's faced racism all my life, I'm half English, half South African, half white and half Cape Coloured but grew up in a very racist area of England. I usually find myself having to start conversations (id probably put that more down to my resting bitch face not making me the most approachable guy), but sometimes people can just be awkward. In terms of the BLM stuff, the political stuff happening in the US at the moment is world news and people from different countries may well just want to hear your opinion on it. However the black jokes are wrong. You're going to meet assholes on your trips, whether its because they are racist or just general pricks, as annoying as it might sound the best thing to do is to just ignore and leave them, go meet other people, don't let some random person who you've just met ruin your time. As awkward as it might be to go up and speak to random people in the hostel, you'll make some amazing friendships from it. Most solo travellers will be very welcoming and will more than likely introduce them to the people they know at the hostel. One suggestion would be to maybe travel not so popular countries (the Balkans excluding Croatia for example). Countries like these don't tend to get so many groups, it tends to be more solo travellers, and I've found that in these situations you'll quickly meet people as no one really wants to be alone in the hostel all the time. i hope you continue you're trip and enjoy every minute of it!