The throat is full of fine musculature that responds directly to nervous-system activation. Under stress, the muscles around the larynx raise their tone — a contraction that blocks nothing but feels like a foreign body.
The clinical distinction matters: in globus you can swallow normally — often more easily than you feel you could — and the sensation is stronger between meals, when swallowing on nothing, and weaker while eating. Genuine difficulty swallowing food is something else and needs investigation.
It is the clearest example of somatisation people recognise in themselves: the tightening before crying, or when you have something to say and don't say it. The same musculature, the same reaction — only sustained.