Honestly I don’t think anyone is in the right here, there are two very valid sides to this argument. OP is correct they shouldn’t have to avoid all social media to avoid spoilers or a game as this is then punishment for them having other commitments. On the other hand people have careers on YouTube and social media, they rely on views to generate an income. No unfortunately a catchy thumbnail draws in more viewers, I don’t think content creators are doing it on purpose to spoil games for other people. It really comes down to shitty algorithms.

I was playing chained echoes and was online talking to people about it and this made YouTube recommend videos of the game to me, including videos whos thumbnails and titles were spoilers. It really sucks but that’s the nature of the beast. The content I accidentally saw couldn’t have done anything different. What’s was it meant to do? Have an obscure name? Then people seeking that content wouldn’t be able to find it and both creator and viewer lose out. Should the thumbnail have not had a boss in it? Sure, then it wouldn’t have generated interest in the video and again same scenario.

Unfortunately for you the responsibility falls to both parties and it is far from ideal. However if one is slightly more so in the right I would say it I actually the content creator, provided it is their job then sorry but they literally have too to make money.