Did you not read the article?
It describes how you can create your own cold storage.

HWs create dependency upon a third party gadget- that is not self sovereignty!

It is very simple to create your own secure cold storage as described in the article.
For more detail see this link-
https://electrum.readthedocs.io/en/latest/coldstorage.html

HWs obfuscate the real core to long term hodling security- the essential importance of storing your seed phrase - HWs do not store your seed phrase.