Yes, 30 Mbps is enough to steam HD videos on YouTube.

Yes, 30 Mbps should be enough horsepower to stream on YouTube. It should even support HD streaming provided your network connection is efficient. A good range of speed for YouTube is 15-20 Mbps so 30 Mbps should be enough for streaming HD videos. You can potentially livestream with 30 Mbps but the video quality may suffer because live streaming takes up more bandwidth. Ideally, if you can get 50 Mbps, that will significantly improve the streaming experience and allow you to stream on multiple devices without slowing your signal down.

YouTube has an exclusive 4k feature that lets you stream at 60 frames per second (FPS). This is a higher-quality 4K experience and If you want to take advantage of it you may need to increase your download speeds to between 48 and 54 Mbps for a smooth and seamless feel.

Other platforms support 30 FPS and you should be good to go with 30 Mbps on those.