On occasion a client will email me with a request to review someone else's work. In the context of a Certified Fraud Examiner, review often (usually) means critique.
I'm compensated well for those opinions. I am (It pains me to say this on a number of levels.) an expert in this type of work. So, when a client asks for my opinion, I approach the review with an open mind, an eye towards compliance, and deference to the people who've done the work.
I have, on occasion, offered my opinion in non-professional settings. A review of a restaurant. A snark about a story. My frustration about a process or system. I've checked that for the most part.
When my opinion isn't directly solicited, I'm not certain it is wanted. So - I try to let things rest. There are times when I feel strongly about baseless bullshit people post to social media. I am tempted to offer up my opinion to "set the record straight." The idea that my calling bullshit on a social media post is going to do anything other than piss people off is disingenuous. I know for a fact that my comment on FB isn't going to change a mind. At best, the people who agree with me will chime in with some form of "amen." At worst, the people who disagree with me will chime in with, "You're an idiot." (That last part may, in fact, be true.)
Another form of criticism that I find nearly useless is the long-form takedown of something created for public consumption. I'm thinking specifically about my education business. We have several content partners who have put hours and hours of their time into creating new and entertaining education products.
The long-form takedown is often veiled (or not veiled at all) in condescension. It's often written in the spirit of, "Let me inform you." Mansplaining at it's best. More often than not, there's an anemic attempt somewhere near the close of the long-from takedown where the writer says something intended to ameliorate the "You should have had me teach this topic, I'm really more qualified than anyone on earth" tone. You'll recognize this when you see phrases like, "I hope this is taken in the spirit it is intended."
A few of pro-tips for those who (unsolicited) love to correct other people's work. First, finish the entire class before you rip the product apart. Second, understand the intended audience. Finally - and this is key - don't be a dick.
Criticism is welcome - constructive and useful criticism.