I used "agreed" a bit, partly due to a coworker, but it's quicker than "I agree", its own thought (unlike "Same"), and it actually elevates the discussion in that using it says--to me--that I am treating that to which I agree as a formal proposal, and I am jointly adopting it ("It is agreed that <what the OP said>").

Agreed implies it's a two sided understanding, context wise.

The latter is more of a person stating an opinion and standing up for himself/herself.

Agreed means you may agree in spirit but not ij action.

I agree is concrete and I can screenshot it and beat you over the head when the project faces a snafu and you try to blame me for all of it.

Ask yo mama

'Agreed' is a word. 'I agree' is a sentence.

The same as queefed and queef.

It means the same. It’s just context.

They're basically the same thing.