Already made that decision. I tried a SDR radio, played with it a while, then got rid of it. Still have a computer. Computer and conventional radio still co-exist.
My computers make me money which I then use to purchase more radios. The two are inextricably linked.
It's also a radio. But in the strictest interpretation of the original question, I would keep the radio and use a paper logbook. That's really pretty easy.
Why does it have to be an either / or situation? I've had a PC in my shack ever since I got licensed. Used one for RTTY and PACKET back in the day, then computer logging. Don't have an SDR radio. Have tried one that we have in the clubhouse at Radio Club of Tacoma. I just can't warm up to the thing... I prefer radios with knobs.