Sounds like conventional lawyer talk to me here. And it is exactly what they want you to think. It plays into THEIR narrative for extorting more money.
What if I told you that most claims NEVER go to lawsuits? What if I told you they routinely lie about the lawsuit thing? And even if the very few go to lawsuit level, they end up getting settled way before a judge gets involved? And in some situations, filing a lawsuit is like farting in the wind. It becomes a win that is entirely noncollectable. If filing and winning a lawsuit was so simple, there would be no need for extortion letters.
The scenario you paint anyone is free to believe and follow. And if someone has more money than actual facts and a true assessment, then they can piss their money away. People piss money away all the time unnecessarily because they never learn how things really work and how to fight back. Or they let their imaginations run so wild and insane, they sabotage themselves.
Just because there is an infringement, does not automatically mean it is "monetary worthy". That is a myth perpetrated by those who drink the spiked kool-aid. There are many images which are free you can't get people to ever pay or use. Period. If you want to pay, go pay. If your client is aching to pay to satisfy his conscience, that is fine.
However, there is a such thing as a "de minimus" infringement which I see all the time. The images are not special or noteworthy and they could not sell it for $5. But because someone stupidly infringes on the image by posting on a website that gets 10 views per month, it suddenly becomes deserving to pay $1,000 or more? I want to make clear that I believe it is bullshit.
I don't condone infringement or piracy but I don't buy into the bullshit line about someone's "ethics" is questionable because they don't want to roll over and pay a stupid/nonsensical amount of money. What I understand about your statement is that it is YOUR opinion and YOUR stance. If you think ELI is infested with ethically-challenged people, maybe you shouldn't be reading the discussions here.
Second, if they do litigate, it looks very bad and increases the chances that a judge will award attorneys fees if the defendant made no offer to settle the claim; conversely, it also makes the Plaintiff look very bad if they are wasting court time when the defendant made a somewhat reasonable offer.
I understand how someone who does not have ethical concerns or is not worried about being sued may wish to ignore the letters or offer nothing, but I doubt that is most people.