Is there some automatic way in Audacity to reduce damages done to music due to loudness war? Or in some other Windows software?
I do not expect it to be perfect- but to just ease / speed up process of further manual reversing of this loudness insanity, which is pseudo-dynamics and clipping. You know: to make a [typical] modern released recording sound more like it was released in the 1980s
I am using Audacity 2.4.2 [but if needed I can upgrade] on Windows 10 Enterprise 20H2 19042.746 x64
Loudness war was increasing amounts of compression.
The opposite of compression is expansion.
Here are 3 free expander plugins which work in Audacity on Windows …
La Petite excite … [Free] [VST/AU plugin] La Petite Excite [says “exciter”, but it’s a (2 band) expander ].
ToneBooster’s FIX … Free (v3) ToneBooster's plugins - #2 by Trebor (6 band)
Steve’s dynamic mirror … Envelope follower / ducker - #6 by Trebor (1 band)
Audacity has [u]Clip Fix[/u] which MIGHT help.
You MIGHT be able to improve the sound but you can’t really reverse the damage…
Sometimes compression is reversable if you know all of the settings/parameters. In the analog days DBX noise reduction used “compansion” and I believe it was also used in analog telephone systems. The signal is compressed before recording (or transmission) and expanded during playback (or receiving). That greatly improves the signal-to-noise ratio and dynamic range. It was never popular because unlike Dolby noise reduction it sounded terrible when played-back without decoding. And of course, digital made it obsolete.
But with music production there are several issues (besides the unknown settings/parameters)… With limiting (and clipping) it’s impossible to know the original height or shape of the waveform. Sometimes multiband compression is used (with more unknown parameters). Often compression is used on the individual tracks before mixing so that’s impossible to reverse if you only have the final mix.
…And, I suspect that much of it is in the performance, arrangement, and playing style. We’ve got a couple of generations of musicians & producers who think music is supposed to be constant-loudness. 
…We can’t have any quiet parts or any louder drum-hits or cymbal crashes, or anything that stands-out from the background!
Does anyone else has something to add?
Maybe there are some advancements in the field of audio AI and some new methods are being developed or recently have become available for usage?
Not yet… Maybe soon… Maybe in a couple of years AI will be able to remake the song from scratch with whatever changes you want!
Still waiting! And with Intel poised to release their line of AI accelerating Arrow Lake processors by year’s end, now would be the ideal time to begin development of a far more powerful solution.
I don’t think he meant something that fancy. But if instruments can be separated with an AI plugin, I can imagine an AI tool that can change those instruments loudness and fix clipping while doing so.
Even the clip fix feature seems to have been removed from audacity.
Accessed by: Effect > Noise Removal and Repair > Clip Fix
Maybe the OP doesn’t but I certainly do. Despite those saying that it’s still in its infancy, given how fast AI is being applied to highly complex biotech analyzing, testing and manufacturing tasks, and to numerous other fields. Of course, accessing AI utilities and consultants cost serious money, and Audacity is hardly a profit motivated endeavor. But here’s a peek at how Izotope developers have tried to undo the damage of overcompressed recordings. https://www.izotope.com/en/learn/inside-ozone-12?srsltid=AfmBOooYShYWw5d17Ao9y9EJxwCjju81qROXD_lWfCxcDL95PuMAj2hB#unlimiter But one would think that Izoptope would have put this kind of utility into their Rx restoration app. In any case, as an audiophile, my dream would be to have the tools for decompressing-or, as Unlimiter seems to do, run processes on the recording which appear to decompress-my favorite music 60s tracks, but doing so with the least audible consequences.
Go to Effects → Plug-in Manger and make sure it’s enabled.
That
Effect > Noise Removal and Repair > Clip Fix
is way too primitive
What I am waiting for are automatic ways for easy de-normalization, a simple method for removing abrupt volume changes
Nowadays pretty much all songs in a breakdown will pump e.g. bass guitar and high hats if it these instruments that stay in it - and when breakdown ends thus suddenly in the same moment vocals and two guitars will kick in, then the bass and high hats will be pulled down immediately. Such changes are extra annoying and noticeable when it is a vocal sound that is being in a split second manipulated by tens of percent - something that is totally absent when you watch a movie from the 1980s and a contemporary song is being played in it
Me not being a fan of dynamics [even in classical music works] is purely subjective - but that artificial / fake dynamics imposed by the music industry during loudness objectively ruined the music in overall
Most “audio problems” can’t be fixed. 
You could try Izotope Ozone (link above) to see if it helps. There is a free trial but it’s a plug-in that doesn’t officially support Audacity so you’ll probably need a different host
