Because "greenwashing" refers to the Saudi's attempts to say that what they're doing is for ecological, climate reasons.

You're right, they are earnestly pursuing both, for exactly the reasons you describe: pure profit.

But Saudi Arabia has implied that they are pursuing green tech for environmental reasons, which is absolutely antithetical to the stance of "let's burn every single drop of oil we can before it stops being profitable."

Because their plan to:

"... lobby against government subsidies for electric vehicles in countries around the world."

invalidates the claims they have made to be earnestly pursuing renewables. Personal transportation is a huge consumer of nonrenewable energy today, and EVs are the shortest path to transitioning personal transportation to renewable energy.

They might be earnestly pursuing both, but actively worsening the problem undermines their credibility in conversations about solutions.