Yes, and no. With your question, you raise another - for whom is his death a sacrifice? Did he sacrifice himself (as a martyr) or did his family sacrifice him?
While The Metamorphosis has many themes running throughout, the idea of liberty is rather prevalent. Could Gregor escape his family and duty? His self-identity seems to deteriorate to the point where he has become something he doesn't want to be - and in the end, he dies, whether from self-loathing, self-sacrifice, or because his family no longer want or need him, or because they have learned to hate his bid for freedom are among the many possible answers.
Yes, because Gregor wanted to lift the burden of his family.