Oh really? While Tom Nichols focuses mostly on the tyranny of being subject to the teaching evaluations of entitled students, my concern remains administrators and politicians. Why? Because these folks tend to be, ahem, craven. They bend quickly to pressures from voters/politicians/lobbies. Academics often will research stuff that is inconvenient: that global warming is happening and caused by humans; that evolution is more than just a theory; that politicians might behave in ways that voters might not like; that there are principal-agent problems all around us; and on and on.
A key feature of the 21st century is the ease of registering discontent via social media. That individuals can say stuff in the classroom or online that gets taken out of context and spun up so that administrators do things like deny a person a job that they have been promised (Salaita), set up policies to punish people who tweet things that are undesired by the state (Kansas), and on and on. It is no accident, I think, that we have had a series of cases where universities have been uncomfortable with the social media activities of their professors. Yet universities and grant agencies want professors to engage in wider dissemination of their work via social media. This circle can only be squared if professors do not fear for their jobs. Tenure provides that protection.
If the complaint is that the end of retirement ages means that we have heaps of profs over 70, then there are ways to fix that: merit increases (unless budgets are fixed)*, carefully designed post tenure review that limits exposure to the whims and fears of administrators, increased teaching loads, etc.
* I am not a fan of the combination of tenure and unions because it tends to take away the ability for institutions to develop incentives--merit increases--to reward and punish those who have job security.
Any "fix" will have tradeoffs. At a time where one politician seeking the Presidency has apparently sought to fire academics who disagree with him (that would be Scott Walker), we ought to be careful about threatening academic freedom. The ability for stuff to go viral means that we all need to be careful before overreacting. The best way to insure that professors continue to operate at the edges of our knowledge, pushing the boundaries of what we know, is to make sure that they don't have to watch their backs. The threat, as we have seen, is real. Lawsuits may ultimate protect us, but I prefer to have a handier shield that enables us to do what we are supposed to do: teach, think, and write freely.