Hello.
On my Ledger Nano I have 5 wallets.
~snip~
You probably don't even realize that you have a much bigger problem because you're using a device from a company that has already had two major data breaches (one recently) involving all customer data. Anyone who still uses their devices should know that they are the target not only of hackers but also of possible physical attacks.
Additionally, you are using a device that can extract your seed remotely and send it to third parties. With all that said, your concerns about legacy addresses seem pretty trivial.
It would be better if he migrated to a brand with a better reputation, such as Trezor, which is plug-and-play, more intuitive, adapted for new users, in addition to being a pioneer in hardware wallets. I recommend buying the Trezor Safe 3 or later (
since previous models are no longer available for purchase on the official website, regarding buying from resellers, make sure to buy from a reseller authorized by the manufacturer), creating a new seed, backing up this new wallet, and gradually transferring funds to more updated accounts addresses, such as p2wpkh or p2wpkh-p2sh.
I believe the OP already got all the necessary answers in this thread, so he should already understand that still using p2pkh (legacy) addresses doesn't make his coins insecure. In fact, it's even good to use all 3 or 4 address types. Some wallets like Bitcoin Core, set the change address type used in the destination address where the user is sending the payment, which even improves privacy a bit.
So OP, you're not entirely wrong in still using legacy addresses, and you don't need to "migrate" funds to updated addresses urgently. Simply transfer what's necessary, taking all necessary precautions such as copying the address correctly (and always checking it, as there is malware that replaces addresses on the clipboard).
Using legacy addresses doesn't represent security risks to you, you'll just pay more in transaction fees (about 40% more in sat/B). I still use legacy addresses, as well as all address types, to improve my privacy on the network a bit.