In practice, though, this turns into a motte-and-bailey, whether or not that is your intent.
When someone today talks about "decolonization", what are the odds that they're talking about Palestine? What are the odds that they're talking about the Belgian Congo? This is especially true if it shows up on Twitter rather than in an obscure journal about the 20th century history of Africa.
So (many) people are using "decolonization" to mean the destruction of Israel. And then (some, and maybe not the same) people are saying "you can't say decolonization means genocide, because there's all this history of Africa and India and the Caribbean and so on - it doesn't necessarily mean that." OK, fine, but these days, on Twitter, what percentage of it does mean wiping out Israel? 95%? 99%?
So, yes, as a matter of definition, you have a point. In practice, Twitter has a point.