You can't prove that Recovery doesn't allow internet access to your wallet even if you don't enable that feature.
It's closed source firmware.
A cold wallet is a device where the keys can't be reached over the internet. Ledger created an API to allow internet access to keys on a Ledger device, and they baked that API into their firmware. Even if you don't enable it, it's a danger to your wallet.
People are going to downplay that danger until it causes them to lose their coins. Then, those same people will be screaming from the rooftops about how they weren't warned about the dangers of hardware wallets having key extraction baked into the firmware.
This is a good critic and you are right. There is a risk.
However, I doubt you consider a hot wallet safer than ledger

Why limit your options to those two, both of which are bad?
Trezor is open source. It's a much better option.
Blockstream Jade is open source and airgapped. It's a much better option.
My own favorites are Krux and ShieldSigner, both of which are fully open source, stateless and airgapped. ShieldSigner is a fork of SeedSigner that adds many powerful features (encrypted seed QR, smartcard support, etc).
Ledger is a terrible choice. I wouldn't recommend Ledger to anyone, ever.
Ledger Live is loaded with trackers. Ledger employees have been phished, causing them to reveal Ledger's closed source code to hackers. Ledger's management lied about many key features of Ledger devices, which forced them to scrub their own website to remove falsehoods. Ledger is a terrible company.