Also @OP, it’s “the combine” the word itself is plural, like fish for example.
The plural of combine is, in fact, Comban.
If I remember correctly in Half Life Raising the Bar. A quote from a cut character (Eli Maxwell or Captain Vance I think) said something along the lines of “Advisors where once a race like us but there over reliance on technology transformed them into a grub like creature”
While this may not be canon. I think it is an interesting concept. I mean Advisors certainly do use technology a lot. For breathing, grabbing and eyesight, and the rest they do with Psionic powers.