But it shouldn’t - as you can have your ICC profile embedded in the PNG.
So there really is no reason to exclude this possibility.
I agree with everything you have said though.
If I’m going to open a PNG to make an edit I’m not resaving it as a PNG - it’s destructive - layers won’t be kept for example (at least I don’t think I’ve seen a layered PNG since Fireworks).
Every situation is different - and every printer is going to be different.
The reasons for 1, 2, 3 and 4 - is simply that the people behind the wheel are just that - driving the vehicle, they are not the mechanics - they don’t know why it works that way - it’s just the way it has always been, turn the engine on, set into drive and steer it and don’t crash.
Unfortunately, it’s more prevalent - mac monkeys running prepress.
What has the best chance of working across all mediums - in my view - it’s PDFX4a.
That is inserting your images as is as supplied - and then the PDFX4a is sent to any printer - who then do the conversion on the fly for their presses.
That’s literally the best way - as you can convert to Coated Fogra 39 - but what if that then they need (as you say you supply files to clients and not printers) - what if - they need to send it to an uncoated paper for printing… or to a digital format?
Let me get it straight that I’m in no way telling you or anyone else that they are doing it incorrectly.
This is purely my experience. And I too have been sending files to print for close to 25 years, and they go globally! Around the World. From printers in Europe, to US, to India, to Australia, to China.
I too cannot have a blanket export settings - it doesn’t work like that.
People see High Quality PDF setting and think that’s great. What people don’t realise is that all these Presets built in are only for Starting Points.
You use your own experience - your own knowledge - your own questions/answers back and forth with clients/printers to make the decision that works for you.
There is no ‘correct’ PDF setting.
Push does come to shove sometimes and I provide a PDFX1a Coated Gracol PDF because some Luddite in a prepress somewhere hasn’t the foggiest notion of what they are doing.
Let me say it again - there is no wrong answer. There is no right answer.
PNG for print - if you want to - it has problems, pros and cons, but I’ve done it for years - using my experience and my knowledge and gotten very good results.
Hence, many many years ago, shortly after dumping Quark, (possibly circa 2001), and took up InDesign - that I stopped converting RGB to CMKY - stopped resaving JPGs to TIFF and all that stuff.
I insert as received. I output to the PDF settings required for the job - which can be different depending on the job.
Should you use PNG?
Why not TIFF?
Yes, PNG if you’re not concerned about colour.
GIF if you want to - no problem with a logo supplied as GIF that’s 2 colours - GIF is a limited set of colours - but if it’s ok it’s ok - I’m not gaining anything by changing from GIF.
But the biggest thing really when it comes to file type is using the one that is most appropriate.
If you’re making edits - then save it as a native PSD or TIFF file.
If it has text/vector masks/vector shapes - then save it as a PDF.
If you want to colour correct the PNG - then of course convert to another format and use that - to retain your colour corrections.
Funny thing is that as a scanner operator for a few years, we always colour corrected in RGB. Which was challenging, but it was far better.

