You employ disingenuous rhetorical tactics. That's doesn't necessarily mean you are a dishonest person. Lots of people use similar or identical tactics. Others either don't recognize the tactics when they see them, or decide it's not worth the effort to point them out.
And your post has yet another example of disingenuousness. The point of controversy is whether it's reasonable to state "Without common ground, 'The Earth is round (or not round)' can be said to be an opinion." Yet you imply that the point of controversy is ignoring the unwritten "IMOs" in statements which are clearly just matters of opinion. But I'll indulge you and address the unwritten "IMO," even though it is not the point of controversy. If it's clear that a statement is merely a matter of personal preference ("DDO needs respecs") then of course there's no need for the "IMO." The problem arises when people state something like "DDO needs respecs" and then base yet another argument on the premise that DDO needs respecs, under the assumption that it's a given that DDO needs respecs.