I've read the thread and it discusses more than one subject. I initially looked at the title, then the linked video before I made my previous posts. I have now read the thread and see it refers to 2 different things, sharpness and focus. It goes into more actually but let's just worry about these two.
Is it ok for an image to not be sharp? Yes
Is it ok for an image to not be correctly focused? No
I'll give examples:
Page one of the thread Dorothea Lange’s famous “Migrant Mother” photograph is mentioned.
Is it good photography? No, it's rubbish. This is a bin/trash/delete job.
Why is Migrant Mother deemed acceptable by the world? Why are the other images presented throughout this thread deemed acceptable? In most cases, it's their content.
There are many well known images that are famous for their content and/or newsworthiness. This does not make them good photographs or suggest the elements within the photograph have been correctly achieved. All technical requirements and rules can be thrown out for this type of image and it will still be successful.
If Dorothea Lange had shot her image on a modern camera, quickly looked at her LCD and found she missed focusing on the face what would she have done? She would almost certainly have taken a second image and thrown the first, now famous one, out.
Photographically, the image is weakened by the woman's face being soft. The image could be improved with more facial detail and sharpness. This isn't an image we are trying to glamorize the model, we are trying to depict the conditions/stress this woman is under and it should be shown on her face as much as is possible. Heck, maybe Dorothy should've applied a little make-up to the model as well???
As an image for photographers to learn from, it demonstrates what not to do and demonstrates what to delete. The image is only strong because of it's content.
In this situation:
Tom Reichner wrote in post #19176502
If I take 20 shots of a deer, and 4 of them have the deer in a favorable pose, and one of those 4 is a bit more dynamic of a pose than the others, and if 5 of the 20 photos are tack sharp and the other 15 are soft ...... then the odds of the frame with the best pose also being tack sharp are rather slim.
In this case, all the photographs may be keepers for Tom. For Tom, the content may have greater meaning than the technical merits of the photograph. Which ones should Tom display on this forum? Likely not one of the 15 soft images. Some of his forum viewers will be looking at the images for their content but almost certainly every viewer will be looking at his images for their technical strengths.
If I take a pic of my daughter and miss focus, yes, for myself it might still be a keeper but that does not make it a good photograph. I'm keeping it for it's content and not because I feel I created a good image.
In the video they are suggesting missed focus is fine in a general context, it's totally wrong and ridiculous to suggest this.
Sharpness is a really open discussion. Focus is not. A great photographic image which other photographers should aspire too will have strength in all elements. The really and truly great images should contain great content and have great technical attributes.
Let's not lose sight of what a great photograph truly is.