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.