Funny, because internet access and TPG resources have provided ample comparison and learning materials. Those who make the effort nowadays might just be more observant and accurate than the previous generation. Their eyesight should also be better. How did they treat cleaned coins back then? Same as in Europe, assign a real grade, just lower it due to the cleaning?
Would that be the same generation that thinks you can grade a coin by looking at pictures ? Let alone tell if it's a problem coin or not
No, but it's the same one that doesn't see every raised line on a coin, in a photo, as "harsh cleaning".
Some collectors are going to be turned off by any problem coin, including graded coins with very minor problems. That's their personal taste, and that's okay. There are many problem coins out there that are still attractive and collectible to a lot of people though. Counterstamped coins were at one time only considered to be mutilated, but now they have a following of collectors that appreciate them for the appeal of their damage. I'm not going to dismiss a coin I find attractive simply because it has a problem, as long as it doesn't carry a problem-free price tag. Don't get me wrong, I strongly prefer problem-free coins and most of my collection is problem free; but I also have many coins in my collection with nice details that have old toned over cleanings, scratches/graffiti, or other damage that I feel add character to the coin. For example, one of my favorite problem coins is a raw choice VF details 1837 bust quarter with an unusual shape (sort of like an upside down bass clef) tooled into the left field on the obverse. Based on the toning, the tooling may be almost as old as the coin. I picked up the coin specifically because I liked the character and the price was fair. Having said that, I have never found any appeal to coins with completely destroyed surfaces from heavy cleaning, over dipping, whizzing, environmental damage, etc.
I guarantee in a few years there will be an "app" where you take a high res photo of your coin and it grades it for you, including if it was cleaned