Steam Developer, I've delved further into the documentation and found that employing disableMobile: true rectifies the issue at hand.
From WIKI:
"disableMobile": false // pass `true` here to have node-steamcommunity not use the mobile login flow. This might help keep your login session alive longer, but you won't get an oAuth token in the login response.
I would like to express my gratitude to Dr. McKay for his substantial contributions and for turning this into reality. His code served as a source of inspiration for me in the past.