Hmm. In the country where I'm from, absolutely, that's the case. The average level of IQ there is incredibly low, so it's not really surprising.
Generally on the internet? Well... kinda yes. Of course, I know there are many cases thanks to social media garbage that are making people unwilling to read and use their brains to think, thus degrading their abilities to pay attention for a longer time, which would be required for reading even just a moderate length of text. Yes, I'm fully aware of that, and that's a tragedy for today's generation.
So why "kinda"? Apparently I tend to follow topics that actually require a certain level of intelligence, and the communities there usually have adequate reading and comprehension skills.
But yes, long story short, that's the trend unfortunately. People just read less and less, and with that, their skills are degrading as well.
Even if someone doesn't use an adblocker for some reason... who the fuck would click on ads?!