I understand why people are mad at PB, they were giving people something for free (yes they had ads but looking at an ad only costs you time not money unless you buy) then after PB found out that their costs were going nuts for what they had to pay for bandwidth and storage they needed to do something.
Now what they did and how they did it was going to the extreme but that is like so many other businesses and governments. A great example was years ago a local government was giving free permits for different things like building & development then they found out it was costing them money so they all of a sudden started charging $100 - $500 per permit.... the costs that they found per permit was $10 - $20 so why the hike so high because they could.
Another one was there was a region that was allowing free camping on government land, People loved it!!! Then the government figured that it was costing them to patrol it so all of a sudden it cost $50 per permit to camp and X $ per night, it was all of a sudden cheaper to camp in a campground with full hook-ups then in the bush.
PB should have found a way to incorporate ads in the images so when you looked at an image on a forum a small ad came up, that would have given them income to offset the bandwidth costs. Or offer a free plan with ads then a paid plan with no ads or smaller ads. They will change their name and prices in a year or two and people will start using them again.