No. John-117 was never a cyborg.
Just because he has a neural interface doesnt make John a cyborg.
Do you know what a Cyborg is?
Yes, I do.
Does MC have a completely metal body under the armor? No. He is just an enhanced human. Hence, not a cyborg.
Umm... that's not entirely what a cyborg is. Any organic being given a mechanical enhancement is a cyborg.
Huum .... no. An external armor does not make you a cyborg. He can fight without it. A cyborg would have mechanical parts, like robocop, not a suit.
They are not talking about his armor, they are talking about the bio mechanical implants, the dendrites in his brain, the carbide ceramic on his bones, the platinum pellet in his thyroid, etc. He is a cyborg even without his armor.
There's several things wrong with this. First of all, unless John's skeleton gets wi-fi or has minesweeper installed, you can't really count the reinforced bones. They're not mechanical or electronic. The Thyroid implant is just a pill filled with hormones that are released into the body as the pellet is dissolved. It's not a permanent part of his body. It's like saying that after swallowing some Tylenol, you're suddenly a Cyborg. Also, we ALL have Dendrites. They're a part of nerve cells.
And EVERY serviceman and woman in the UNSC has a neural implant. Spartans, at least IIs, just have better ones. If anyone is a Cyborg, it's probably the Spartan-IVs. In addition to having the standard neural implant, they also have an implant that monitors their vitals and whatnot.