To me, "most" implies "at least 95%". That's because it's used to exclude a possibility: If most programming languages have if statements, then if I hear about your new language I can assume it has if statements without checking further.
To use a simple majority means that you'd have to accept a simple statement like "Most programmers use Javascript"[1], and that's too weak to use for any reasoning.
I asked a few friends how they use the word, and apparently there are people that use it to mean "nearly all" and people that use it to mean "more than half", and the first group doesn't realize the second group exists.
This paper[1] gives a couple interpretations, none of which are as strict as the one I use. I wonder if I mixed up "conversational implicatures" with a heuristic for logical implication.
In any case, I've apparently been wrong about the meaning of a basic English word my whole life, and I can't find a good cover story to hide the mistake.