This is the Woodward school of thought. He has no value now, he’ll have no value at the end of his contract so just renew the contract and hope he finds some value at some point. Spoiler: he never does and we waste millions in wages.
It’s not worked, he has very little value now, he will have zero value in a few years when he’s played less and regressed even more. Take the peanuts today before we end up paying him to go and play somewhere else like Donny, and everyone else we’ve moved on in recent years.
If Antony was to regain some value he’d be the first player post Fergie to do so. You can’t run a transfer policy on hopes and dreams.