There is still some trust hidden away in step 10 that you didn't call out, which is that you're trusting the software wallet. The software wallet that you use

There is still some trust hidden away in step 10 that you didn't call out, which is that you're trusting the software wallet. The software wallet that you use to create the transaction could under the hood create a different transaction than what you expect and show you the hash of that transaction. A hardware wallet that signs a raw hash will always be vulnerable to this kind of attack. To really eliminate the need to trust the software wallet, you should send the whole transaction to the hardware wallet so the hardware wallet can calculate the hash. You're still trusting the hardware wallet to some extent but you entered your seed phrase into the hardware wallet so you're implicitly trusting that no matter what.