When I've set up static shots - like talking head stuff or product reviews - a tripod does the job perfectly fine and costs way less. You get rock-solid framing, which is honestly what most YouTube creators rely on for the bulk of their content. A gimbal shines when you're moving around, like walking while talking or following action, because it smooths out all the little bumps and shakes that make footage look amateur. But that comes with a learning curve and you're carrying more gear around.
For someone just starting out, I'd go tripod first. It forces you to think about composition, lighting, and camera angles before you press record - which are the fundamentals that actually matter. Most beginner YouTube channels do fine with a locked-down tripod setup. You can always add a gimbal later when you've figured out your actual style and know you need dynamic movement. Plus a decent tripod is under fifty bucks, whereas you're looking at several hundred for a gimbal that works well with a mirrorless camera.
The real question is what kind of videos you're making. If you're doing sit-down tutorials, reviews, or anything scripted, the tripod covers you completely. If you're planning vlogs or lots of walking-around content, then yeah, a gimbal becomes more useful. But honestly, start simple and see what you actually need once you've made a few videos.