Most of these systems were probably made when you were still using dial-up. I'd guess that a majority of them aren't even supposed to be used through the web but through proprietary desktop software. Any website that you can access the data through was slapped on top of what was already there. It's kind of a miracle that you can get at this data at all without having to write a FOIA request and wait weeks for it to be mailed to you.
Another thing to keep in mind is that while Tyler deals with a lot of data that's "public" (in that it's paid for by tax dollars) the main customer for most of their software is not the public itself, but the government employees that use it. They know that this is a problem and I'd like to say that they're working on making it easier to access, but I don't know for sure since the company is absolutely MASSIVE. Way bigger than you'd ever imagine.
Not trying to defend the fact that this data was hard to get at, just hoping to maybe give some context. Data should be free and easily accessible to all.