The verses in the Maṅgala Sutta can be interpreted in mundane ways and with deeper meanings. The Sutta Central translation you quoted interchangeably uses both types of meanings.
“Bāhusaccañca sippañca, vinayo ca susikkhito; Subhāsitā ca yā vācā, etaṁ maṅgalamuttamaṁ” is translated there as, “Education and a craft, discipline and training, and well-spoken speech: this is the highest blessing.”
“Sacca” is truth, and “Bāhu sacca” can be interpreted as “figuring out the truth by analyzing Dhamma concepts in various ways.” The more ways one can look at a given concept (from different angles), the better. That is a deeper meaning.
“Sippa” is translated there as “craft” and in the “Sippa Sutta (Ud 3.9)” as both “craft” and “professions.” Both meanings are correct. However, the deeper meaning in the Maṅgala Sutta can be interpreted as attaining iddhi (supernormal) powers, going through walls with the manomaya kaya, etc., i.e., as “extra capabilities.” Those are not necessary to attain Nibbana but are “added capabilities.”
At the end of the “Sippa Sutta (Ud 3.9)” (@marker 6.1), the Buddha advises bhikkhus not to engage in other mundane professions/skills.