As for Leonardo DiCaprio, he has even fewer TV credits than Pitt, although he actually had some decent runs on some shows.
Most of his contributions to TV have been in executive producing capacity.
His latest TV appearance was as himself in a Saturday Night Live cameo.
Brad Pitt appeared in eight episodes of Comedy Central’s The Jim Jefferies Show as the very depressing Weatherman starting in 2017, but I’d say that hardly counts as a high-profile project that showcases what made him famous.