There’s no reason not to have a passion for both. I have been into cars all my life. A bad mtb accident in the 90’s put an instant stop to my cycling. Early 00’s I rescued a really good bmx from a neighbors trash and was back on a bike for the first time in years. My kid raced bmx so I got myself a race bike to ride with him. Last year I rediscovered road cycling and am hooked. I have a few vintage bikes and a modern one.
But during all this time I never stopped building cars. I have an ‘83 grey-market Benz and a ‘91 first gen Montero. I will always be a car guy and I believe I will remain a bike guy the rest of my days.