Perhaps in the past, but the NSA are good at predicting trends. They know that something broken by a supercomputer today will likely be broken on a smartwatch

Perhaps in the past, but the NSA are good at predicting trends. They know that something broken by a supercomputer today will likely be broken on a smartwatch tomorrow. Intelligence agencies, unlike most tech firms, need to futureproof their secrets for decades. While the NSA no doubt has an interest secret backdoors, I don't think they would today support mathematically weak encryption.