Speech enhancement (denoising/dereverb) and seperation is absolutely a hot research topic, as it's needed for fields like voice assistants as well. Unsurprisingly, the state of the art is variety of deep neural networks, here's a good overview of recent developments [1]. Of course, many of these are far from real time, but earlier techniques are used in some digital hearing aids iirc. Apple have also released [2] some details of the system the Homepod uses, along with audio samples.

A quite interesting further development of these is this paper [3] which uses brain activity to determine which particular speaker the listener is trying to hear, and then optimises that.

[1] https://arxiv.org/abs/1708.07524 [2] https://machinelearning.apple.com/2018/12/03/optimizing-siri... [3] https://advances.sciencemag.org/content/5/5/eaav6134