There is another part to it. The democrat constituency loves that 'class warfare rhetoric'. The democrat politicians know it doesn't work for all the reasons you mentioned but they don't care, it keeps getting them elected. And, that is the most important thing to a politician. Term limits would do wonders for this 'Republic' of ours.
I think term limits can deprive us of some good people. The same goal can be accomplished by defining and narrowing the rules each house is able to impose upon itself. For example, take away the power of seniority by having committee and subcommittee chairmanships rotate each session rather than automatically going to the highest seniority. That would devalue seniority and the power it brings with it thereby giving less incentive to keep getting elected.
Eliminate secret holds that members put on appointments, etc. The abuses occur because of the "courtesies" that members extend to each other. There are many others most of us don't know about.
In other words, it is a good ole boys club which enhances the ability of members to keep getting reelected. It is "You scratch my back and ... " An example is the irritating (to me) habit of addressing colleagues they can't stand as "My good friend, the Senator from the great state of ...."
Eliminate those abuses and the problem is solved without losing valuable experience and good solid politicians. Of course you are asking those who developed and perpetrate the system to change it, just like the tax code.
However, public influence can affect them and with email, faxes, and cheaper telephone calls it is much easier than before. We should do it and do it often.