If you’re mainly making reels and social media content, I’d honestly go with the iPhone first.
Modern iPhones are already more than good enough for Instagram/TikTok content, especially if you’re a beginner. The biggest advantage is convenience. You’ll actually film more consistently because everything is fast, simple, and optimized for social platforms already.
A professional camera can definitely produce better quality, but it also adds a learning curve with lenses, lighting, focus settings, file transfers, editing workflow, etc. A lot of people buy cameras and then barely use them because the process becomes friction-heavy.
For product content specifically, lighting matters more than people think. A good phone + good lighting setup usually beats an expensive camera with bad lighting.