I think it's important to emphasize that all of vulnerabilities that is reported by Ledger security team pose a threat for Trezor hardware wallets only in case hackers come into physical possession of device. Trezor also say that this attacks can not be performed without specialized hardware,
This cannot be stressed enough. [The first vector involved an attacker buying a Trezor, modifying it, and returning it, but this relies on the assumption that Trezor would resell what they believe to be an unopened Trezor without additional inspections, and I do not believe this to be a valid assumption]
as is demonstrated by Ledger it was possible to guess value of PIN with Side Channel Attack in just few tries. Users of Ledger Nano S know that 3 times entered wrong PIN wipe device, but Trezor have 16 tries before wipe, which is too much.
The attack in which Ledger claims to have "guessed" the correct PIN in only 5 tries is claimed to be unexploitable by Trezor:
Findings
Our security analysis found that, on a found or stolen device, it is possible to guess the value of the PIN using a Side Channel Attack. This Side Channel Attack consists of presenting a random PIN and then measuring the power consumption of the device when it compares the presented PIN with the actual value of the PIN. This measurement allows an attacker to retrieve the correct value of the PIN within only a few tries (less than 5 in our case).
Although these vulnerabilities were unexploitable, we fixed them anyway.
It is unclear as to the technical nature of this alleged exploit, but reading the description, specifically, "with the actual value of the PIN" it doesn't look like an attacker could reverse engineer the PIN without existing knowledge of the PIN.
Perhaps the conclusion in this story is that users need to set up passphrase on hardware wallets, but this option is often recommended only to advanced users.
The passphrase is only a password that cannot be reset, and can be more "simple" compared to "password" standards because an attacker cannot try any passphrases without physical access to the device, and there is no way of knowing how many passphrases there are that contain anything of value.
The passphrase is not a very complex concept, and is only marginally more complex than the rest of the recovery seed, and I believe there is a line for the recovery seed should not be limited to "advanced" users.
I've got some coins that have no plans for several more years that are currently on a hardware wallet. I think they're headed back to paper.
A paper wallet is less secure than a Trezor with the cited exploits. A trezor allows a user to use a passphraise, so if someone gained physical access to your "wallet" all they would need is the passphraise if you are using a paper wallet, and would need the advanced equipment and technical knowledge to exploit the trezor.
An attacker may not even need physical access to your "wallet" to gain access to your paper wallet because they may be able to look at your printer to get your "wallet" or your wallet may be as vulnerable as your computer is, depending on the specifics as to how you generated the paper wallet. These vulnerabilities do not apply to any hardware wallet. You also have a higher risk of loss of funds due to things like flooding as your paper wallet may get damaged beyond being able to access the private keys if it gets wet, but is not the case for a trezor (to my knowledge).
You can also not ever spend coins on a paper wallet without loading the private key onto a potentially vulnerable computer. With a trezor, using a trezor on a compromised computer alone will not result in a loss of coins. If your computer is compromised, you should still take care of this.
