Conflict of interest: V. Cottin reports grants from Boehringer Ingelheim, consulting fees from AstraZeneca, Boehringer Ingelheim, BMS/Celgene, CSL (Behring, Vifor), Ferrer/United Therapeutics, GSK, Pliant, PureTech, RedX, Roche, Sanofi, Shionogi and Vifor, lecture honoraria from AstraZeneca, Boehringer Ingelheim, Ferrer/United Therapeutics, Roche and Sanofi, travel support from AstraZeneca and Boehringer Ingelheim, advisory board participation for Galapagos, Galecto, GSK and Molecure, and a position on an adjudication committee for Fibrogen from 2022 to 2023, outside the submitted work. M. Kolb reports grants from Boehringer Ingelheim, United Therapeutics and Structure Therapeutics, consulting fees from Boehringer Ingelheim, Roche, Horizon, Cipla, Abbvie, Bellerophon, Algernon, CSL Behring, United Therapeutics, LabCorp, Structure Therapeutics, AstraZeneca, Pliant and Avalyn, lecture honoraria from Roche, Novartis and Boehringer Ingelheim, payment for expert testimony from Roche, advisory board participation with United Therapeutics and Fortrea, and reports a leadership role as the former Chief Editor of ERJ, for which he received an allowance.