The trousers are probably the most tailored part of the outfit: high rise, deep pleats, extended waistband and side adjusters. But Poszetka makes them in Irish linen, removing much of the formality those details usually imply.
The same happens above. A pale seersucker workshirt replaces the dress shirt. Even the herringbone tie is linen. And a Drake’s × Sebago cap can interrupt the whole thing before it becomes too resolved.
What remains of tailoring is mostly structure: the waist, the pleats, the proportions, the tie. Perhaps summer tailoring is less about dressing formally than keeping the grammar while changing the materials.