They're only boring if you get more than one of them together and they start talking about their coupon/shopping shit. No joke, this conversation actually took place with two twenty-something ISFJs dudes that I know.
Otherwise they're good fun. Pleasant, socially competent people for the most part.
^^ your first paragraph above tends to represent any "boring" times I had with them. Or when my mom and I get together, and she just basically starts rambling through the mundane details of her day and the days of all the people she cares about. For me, it's like all this linear detail is being tossed out me without any real context or shaping or purpose, and it goes on and on... and I'm not even an auditory learner, really, I get bored easily when someone just talks and especially if the data is not structured.
The funny thing is that I only really found ISFJs boring when I was a teenager, but as I got older, I found them more interesting. I think that might have been a change in them, but also in me, where I was more interested in some of the things that used to bore me.
Also, some of my ISFJ friends can develop a really dour/dark sense of humor that I find amusing. I like their realism, and they tend to call things exactly as they are, on the detail level. And what's really neat is when the straight-laced ones end up doing things I did not expect. My ex, for example, surprised me by spontaneously doing things like shooting guns with friends, or getting into fast driving, or renting jet skiis. I love being surprised, when someone normally very constrained just cuts loose.
In general I find them loyal and dependable and considerate and not ones to make conflict just to be contrary; and I typically know if I need them to do something, it will get done and done as well as they can do. I like that stability and consistency.
Did you know that nearly all interesting facts are 95% more likely to interest you than boring ones?
I find that the boring facts are 82% more likely to bore me than the interesting ones.