“Kodak Tri-X is the most famous film of all time, it has a look in it that is easily recognizable.”
“Since typical street shooters need to capture fast-changing moments, the faster the film the better.”
Over the years, Olympus has improved their grainy film modes over and over again. In the Pen f, the black and white filters can end up looking like Ilford Delta 400. But in the OMD EM1 Mk II, they resemble Tri-X a bit more. The only other company that really is able to pull off anything that looks remotely like film is Fujifilm–at least at the moment they are.