mw13,
I think you are correct in principle, but one cannot understate the difficulty and risk in properly giving tochacha to a Jewish soul. That is why, I think, you are receiving objections to your post. The Kohen Gadol must enter the Holy on Yom Kippur in a very precise fashion… any mistakes can be disasterous. I think giving tochacha should be approached with the same fear and awe. If a valuable ring fell into the sink and was perched right over the drain, we wouldn’t just quickly swing our hand down to grab at it… we would very carefully and deliberately rescue it.
In some cases if one is careful enough, tochacha can be given indirectly, without any confrontation. To make a really simplistic example, suppose person A sees person B doing something forbidden on Shabbos, like getting something out of his locked car. Maybe later, person A can casually bring up as part of a conversation, “oh, I wish I could show you my such-and-such, but I left in in my car and can’t get it until after Shabbos!” Point made without doing anything to person B’s dignity.