You go on about this in almost every post you make - it's a form of virtue signalling that you obviously love - but I think we shall find that it is you who is clinging to your faulty understanding of the text.
That is absolutely fine, so long as everyone is aware that the words 'those of' do not appear in any ancient manuscript.
This is fine too. I'm sure we're all grateful to you for telling us that 'propitiation' is a noun.
Where do we see the word 'only' in either 1 John 2:2 or 1 John 4:10? Nowhere! I agree with you that Christ is the only means by which sins are covered, but that is not what either text is actually saying. It is what you
want the text to say. 1 John 4:10 is about the love of God in sending the Lord Jesus. 1 John 2:2 simply declares that He is the propitiation for our sins, and not only for our sins, but for the whole world.
Now, for the umpteenth time, the text does not say that the Lord Jesus is the propitiation for the sins of every person in the world; you are reading that in to support your own incorrect viewpoint. But if it did mean that then God is propitiated in respect of all the people in the world, which plainly, He isn't (e.g. John 3:36).
Actually, I haven't said what I believe the verse means yet. Be patient! It's coming. First, I want to show what it
cannot mean.
Again, I haven't said that Christ being the propitiation for the whole world means that all will be saved. What I am saying is that
if He is the propitiation
for all the people in the world then it must follow that all the people in the world will be saved. But of course, the text doesn't say that. It's just what you really, really want it to say.
What the verse does is to refute universal atonement.