Microphones. If you want to create content of some sort and are looking to invest in audio, buying a super cheap microphone won't get you far. There won't be a huge difference (if any) compared to your phone mic. Buying a mid-tier microphone will serve you much longer.
I've been a Redditor for 12+ years, but I will definitely keep hanging out here and I'll keep being active. The community here right now reminds me a lot of the good things of early Reddit, and I like that.