Again, that would need to be a new standard that all payment providers honour. Not to mention 3DS is an optional extension for providers. The dodgy ones aren't

Again, that would need to be a new standard that all payment providers honour. Not to mention 3DS is an optional extension for providers. The dodgy ones aren't going to provide either 3DS or a secondary "are you SURE you are ok with recurring payments?". The legit operators are already making it obvious when something is a recurring payment. The only secure way of getting customers to affirmatively consent to recurring payments, that I can think of, is a separate CVC or similar that's printed on the card. Still, I don't think this is a major problem worth solving. Most customers signing up for recurring payments are aware of what they're doing.