Ideological affiliation is easy to determine. You just ask people which party they belong to. Or who they voted for.
Unfortunately, the conservatives DO have a legitimate concern. A recent study of the political affiliation of professors at the top US liberal arts colleges found that 80% of them had essentially ZERO Republican professors.
"The political registration of full-time, Ph.D.-holding professors in top-tier liberal arts colleges is overwhelmingly Democratic. Indeed, faculty political affiliations at 39 percent of the colleges in my sample are Republican free—having zero Republicans. The political registration in most of the remaining 61 percent, with a few important exceptions, is slightly more than zero percent but nevertheless absurdly skewed against Republican affiliation and in favor of Democratic affiliation. Thus, 78.2 percent of the academic departments in my sample have either zero Republicans, or so few as to make no difference."
https://www.nas.org/articles/homogenous_political_affiliations_of_elite_liberal
On the other hand, the majority of Americans are conservative.
https://news.gallup.com/poll/225074/conservative-lead-ideology-down-single-digits.aspx
The failure to understand this simple fact explains the shock waves that rippled through the liberal community when Trump was elected. Liberals have long claimed that they represent the common man, those who are downtrodden by the big corporate elites. The widespread support for Trump in the traditional blue collar American community felt like a stab in the back to American Liberals. However, the liberal community has always been predominantly elitist and their leadership has primarily come from academia. That's why you hear claims that Trump supporters are stupid and uneducated.
It's important to note that this happened before in 1930's Germany. The German working class overwhelmingly supported Hitler against the far more liberal Social Democrats. The National Socialists were ultra conservative, strongly Christian, homophobic, anti-abortion, xenophobic, and patriarchal. They supported gun rights, nationalism and a strong military. They put traditional nuclear families at the center of their society. Their anti-Leftist rhetoric sounded almost exactly like modern accusations made by Trump supporters against Liberals. In short, they were everything that modern liberals fear. That's why Trump has been compared to Hitler. And liberals are right, his values pose a threat to their values.
These struggles are actually very old and perfectly natural. Urban life and academia naturally produce liberal values. Country life and manual work naturally produce conservative values. But the historical balance is changing. In past times when 90% of people worked on farms or in small factories, liberals were a distinct minority in the general population but a large part of the academic and elite community. Modern technological advances have reduced the farm population to under 5% and eliminated huge numbers of manual jobs. This creates an enormous disaffected class who will naturally gravitate to liberal values. This may or may not be good, we're in uncharted waters.
My concern is the relentless modern leftist attack on freedom of speech. George Orwell famously said that freedom is the ability to say that which others do not want to hear. His books 1984 and Animal Farm came out of his experiences during the Spanish Civil War of 1936. That war can be regarded as a classic example of the Liberal/Conservative, or Fascist/Communist struggle. Orwell obviously modeled 1984 and Animal Farm on Communist dominated Soviet Union, an ultra leftist society where even the slightest anti-government comment or 'denialist' statement could get you sent to the Gulags. Make no mistake, Leftist values come right out of the Communist Manifesto. Abolition of religion, free abortions, easy sex, women's rights, free education and medical care, abolition of racism, nationalism, ethnic solidarity, abolition of corporations, state ownership of everything. Key is the absolute intolerance for freedom of speech.
Leftism has not always been against freedom of speech. But when it has, watch out! Freedom of speech is like the canary in the coal mine. When it dies, death looms over everyone else.
We're in uncharted territory. It will be interesting to see what happens.