Your question contains a noun phrase as a direct object, in bold, which "states" and "asserts" a fact. It matters not that you posed this statement within a question because your usage invites the reader to rely upon your apparent belief in its truth.
So my initial response to why historians seem, at least to you, to be "intimidated" by the fact you assert, i.e. that a traditionally Hebraic population of Ireland and Britain exists or existed, is that your asserted fact is contrary the genetic anthropological evidence, which is so legion and easy to find that I will not waste my time trying to explain it to you.
The other more apparent reason for this intimidation you perceive, less apparent to me quite obviously, is that historians are quite good at avoiding pointless discussions with wackadoodles like you that spout propositions that are unmoored to fact or reality.
I have invited you to state a factual basis for your assertion that "a traditionally Hebraic population of Ireland and Britain" exist or ever existed. You have not. So our discussion is over.
In the “evidence is optional” world, logic is also optional.
So smuggling a conclusion into the premise of the argument is “good reasoning”.
So is its close cousin, the fallacy of the complex question. And basically every other form of bad logic.
Once you realize that these wizards are immune to reason it pays to enjoy them for their entertainment value. Count the logical fallacies and take a drink every time that you spot one. Good luck staying sober.
Look at the word “question” my post #7.
Think about what it means. Never mind, I’ll tell you. It shows I’m designating what follows the word as itself a question, not an assertion of fact.
Again, your use of “wackadoodle” is an indication you have no confidence in your own position.
Confidence in one’s argument pertains to the objectivity of the argument and does not give rise to any subjective state of desiring to call the other person a wackadoodle.
What does give rise to such desire is the feeling of loss—fear—that your assertions are baseless.