(Just to make clear, I'm just trying to learn and understand and don't claim to be right.)

Your 300SP is included in it and allowing you to get bigger upvotes, that you wouldn't be getting otherwise.

ok, the way I wrote that was a bit confusing (to make a real comparison the 300SP total upvote value also needs to be included in the 27.28$), obviously the 300SP is included in the 86.45$ which is the reason it can't be used as an example.

And with all due respect, your argument and comparison with the 10x selfvote is not really an argument.

Why not ? Pure theoretically to me it's one of the comparison that makes the most sense.
(I'm not saying someone should go upvote themselves 10x though.)