De Lie comes from Lescheret, a village in the Belgian province of Luxembourg, and races under the nickname the Bull of Lescheret. He won the Belgian junior road race title in 2019 and took bronze in the road race at the 2020 European junior championships. A season with Lotto's under-23 squad in 2021 brought Omloop Het Nieuwsblad Beloften and the overall win at Okolo Jižních Čech, and he was promoted to the senior team for 2022.
Most of his wins come out of reduced groups rather than full bunch gallops. He is a big rider who gets over short steep climbs well enough to still be there once the pure sprinters have gone, so the Belgian and French semi-classics suit him. His first professional win came at the Trofeo Playa de Palma in January 2022, ahead of Juan Sebastián Molano, and the Grote Prijs Jean-Pierre Monseré, the Volta Limburg Classic and Schaal Sels followed that year.
Lotto Soudal were relegated out of the WorldTour at the end of 2022 despite De Lie finishing as the team's leading points scorer, and much of what came next was raced for invitations. His first WorldTour win arrived at the Grand Prix Cycliste de Québec in September 2023, taken from Corbin Strong and Michael Matthews on a circuit that climbs all day.
A crash at Le Samyn in February 2024 was followed by months in which nobody could account for the missing power. Blood tests eventually returned Lyme disease, and he was treated with antibiotics before rebuilding. He came back to win Tro-Bro Léon on the Breton farm tracks in May, beat Jasper Philipsen and Jordi Meeus for the Belgian road title in June, and took the overall at Danmark Rundt in August by one second from Magnus Cort.
Through 2025 he won the Renewi Tour, three seconds clear of Mathieu van der Poel, settling it on the final stage into Leuven. He added the Bretagne Classic, the Grand Prix de Wallonie and the GP Impanis-Van Petegem, and at the Tour de France he was third on a bunch sprint behind Tim Merlier and Jonathan Milan.









