Is the poet in ‘Digging’ unhappy that he is not a potato farmer? Why

Seamus Heaney's poem "Digging" analyzes three generations: the poet himself, his father, and his grandfather. While the poet's father and grandfather dig physically, the father "stooping in rhythm through potato drills" and the grandfather "going down and down for the good turf," the poet himself digs in a different way, his implement the pen "between my finger and thumb."
Certainly, there is a sense of fond nostalgia for the process of digging, which Heaney describes vividly, using evocative sensory details: "the cold smell of potato mould, the squelch and slap / Of soggy peat." Potato farming is part of the speaker's heritage, the "living roots" of his family. The speaker is not fitted to this type of work, saying he has "no spade to follow men like them." However, his concern about this seems fleeting: the poem does not dwell upon regret, and its tone, while reflective, is not melancholy. Instead, both the beginning and the end of the poem circle back to the idea that the poet digs metaphorically as his forefathers dug literally, contributing in his own way with his pen—"I'll dig with it."