I don’t think it’s difficult to understand that people feel moved by atrocities that are closer to them. The UK directly helped create present day Israel and the colonisation of Palestinian land. Our current government also supports Israel in their attack on Gaza, meaning our taxes are being used to fund weapons and aid the genocide that’s happening right now. Of course people are protesting here.
Does it mean people don’t care about Tigray? Or course not, but we have less direct influence over what’s happening there.