Well there are different tools to clear up a audio track.
$50 will get Audio Cleaning Lab. If I was home I would do a quick auto clean and then hand scrube the file. http://www.magix.com/us/audio-cleaning-lab/detail/
$1199 will get you iZotope’s RX. I actually normally get better results form the $50 one then when I use this tool at a friend's shop. https://www.izotope.com/en/products/repair-and-edit/rx-post-...
Spectral editors are amazing for removing certain sounds and keeping the over all sound intact. This is where we need to move into. Editing at the Spectral level, which will have a much higher CPU overhead.
Here is a great article showing the different hands on techniques for noise removal. https://www.soundonsound.com/techniques/noise-reduction-tool...
To me it sounds like we've got some room for improvement all-around... but color me impressed. I'm also always impressed by Audacity's noise removal when I use it for stupid simple voice-overs. I'd bet this deep learning approach will do nothing but improve, quickly.