Malware vs Ledger Nano S (and other hardware wallets)

A few years ago I bought a new Ledger Nano S so I do have experience using it.

I can fairly assume that I have malware on my Linux pc due to being victim of cryptocurrency phishing. I'll never use the pc again (and neither my modem). Also I filed a support ticket to Ledger including an error log.

Because of the aforesaid I also have difficulty trusting my Ledger Nano S now. I did see some weird things while using Ledger Live (hence my error log). The following post also makes me paranoid: /r/ledgerwallet/comments/u1u9p4/lost_59_bitcoin_because_of_malware_on_my_ledger/

Interesting here are the comments made by researcher of the case u/webblast. E.g.:

"original ledger files were overwritting with other code made by a hacker or criminal and that code generated a btc address that was shown in both ledger live and ledger nano as send address…"

Here it is meant that the user created an address which was also shown on the Ledger Nano S itself, i.e. the malicious address. This makes me believe that I can't safely factory reset the Ledger Nano S (since code could have been modified). When a pc has malware on it a quick factory reset doesn't remove sophisticated malware in all circumstances. So why would it work for a Ledger Nano S?

100 percent cyber security does not exist. This brings me to the following:

I remember that years ago it was said that it is safe to buy a Ledger on the secondary market. I believe even Ledger said one could do this if you inspect the device for physical modifications. And Ledger did say one can use the Nano S with a pc that has malware on it. At that time I understood this as that malware cannot modificate the Ledger Nano S device itself.* But now I think I was naive believing that, since again: 100 percent cyber security cannot be guaranteed. One can only try to mitigate risks.

The point I am trying to make: are you convinced that I can still use my Ledger Nano S using another pc and modem? If so, how can you be given the aforesaid points?

As I am paranoid I would rather have a new hardware wallet now. But the statements made by Ledger makes me want to start this discussion here.

*That's why I felt safe using the Nano with a Linux pc.