I would say that both the plays support the view that tragedy enables audiences to deeply feel the chaotic life of the protagonist. In both plays, the protagonist lets his illusions about how he feels life should be interfere tragically with the reality of how life really is. This causes chaos in both men's lives and psyches.
Lear wants to believe that his daughters truly love and cherish him. He also wants to believe that hearing flattering words of total devotion from them means they really do love him: he wants to believe that words exactly match reality. Because of these illusions, Lear rejects his youngest daughter, the only one who really loves him, because she won't say the right words of love. He divides his kingdom between his two older daughters, not realizing they are lavishing false praise and love on him only in order to seize his power.
Willy Loman also believes in illusions. He clings to the idea that in America a person can get rich quickly as a salesman with nothing more than a good personality. He never wants to accept the idea that success is based on hard work and expertise.
Lear's illusions bring chaos into this life because his two eldest daughters quickly reject him and throw him out in a raging storm. He wanders on a heath, half out of his mind, learning too late that he should have trusted deeds, not words. His mistake costs him his own life and the life of Cordelia, the daughter who truly loved him (not to mention his two treacherous daughters).
Willy's illusions cause him to ruin the life of his beloved son Biff, for he discourages Biff from studying in school, believing personality is the key to success. He also disillusions Biff by having an affair, which ruins his son's faith in him. Willy, who would have been happier and more successful as a gardener, brings chaos into his own life by following his illusions. He never gets the money he dreams of and is never as well-liked as he believes, and he finally commits suicide so that Biff can get his insurance money and have a second chance at success.
For both men, the chaos is manifested in mental instability: Lear goes half crazy from his experiences, and Willy is often delusional.
Both plays fully explore the minds and hearts of their tragic protagonists, enabling audiences to deeply feel the chaos and pain they endure from their decisions.