So what's the difference between a representative republic and a democracy? Are you actually actually saying that for a country to be democratic all government decisions would have to be made by everyone?
The last true democracy was Athens, I believe. At least well-known true democracy.
In a representative republic, we elect people who then make decisions for us. Much better system for a lot of reasons. One reason is that crowds have a tendency to be very emotional and fickle.
As in this thread, most people don't know the difference between a democracy and a representative republic, or why a bicameral legislature has certain values over a unicameral one.
As you point out, even in a representative republic, it becomes easily possible for representatives to compete to form voting blocks in an effort to get more resources than other voting blocks. It doesn't take very long for the system to begin eating itself.
"funadmentally incompatible" seems a little extreme to me, but I'll agree there are worrying tendencies.