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Regarding every generation in Genesis, there is always, and only, one father we can find the paternal years for. We can’t do that for Ishmael and Esau.
Why might that be the case when they also had sons?
[Note: Here Ishmael’s only shown ages are that of 13 when he was circumcised (Gen 17:25) and that of his death at about 137 (Gen 25:17). As for Esau, only his age of 40 at marriage is shown (Gen 26:34)].
From a Christian Perspective, there is a lineage from Adam to Yeshua (Jesus) in which we find righteous men who sought after and followed God; this forms a red line of redemption from Adam (and Eve) whose seed God promised would crush the serpents head, to Jesus who it is believed will fulfill that prophecy.
Generally, the way the book of Genesis is written, the plot forms around these main characters who seek after God. Other branches are referred to, traced to a degree and then allowed to drop from focus; while the story is always picked up again and carried forward through the main genealogical line.
(Visuals like Adam's Synchronological Chart make this easy to grasp, because you can actually see all the other lineages fall off).
In the book of Genesis, the ages of men in the genealogies help form a timeline that provide the historical context/framework for the story. (Note this republished work which provides updated scholarship supporting this view.)
the men you mention are not from the lineage through which the story is carried forward. Their ages were not necessary to establish anything else in the story.
