I don't think they bought them just for the claude-code gui harness as it is now. it's to have strategic control over some software runtime they can use to do other things related to verification, deployment, and end to end value delivery. Same reason other companies are buying up dev tools.

I suspect it's at least partly akin to OpenAI buying uv where they did not want a startup with questionable profitability horizons that serves as a critical piece for their business to get suffocated when VCs come for their money back.