Can you really play guitar without music theory?

You can strum, but you won't truly play. Just reading tablature makes you a 'tab player' - I used to be one. It gets boring, like muscle memory exercises without understanding why you're playing certain notes. But it's enough for casual fun. If you just want to relax or jam with friends, that's perfectly fine. Enjoyment matters more than skill. However!! Even as a 'tab player', you must understand basic rhythm. Without steady rhythm, it won't sound good. I made an online metronome that supports custom rhythms. For tricky rhythm patterns, program them in first to hear how they go before playing along. To sound good without music theory: keep steady rhythm, clean notes, add some technique and feeling. That's enough for most hobbyists. Wishing you a wonderful musical journey!