I just read Umberto Eco's 'Ur-Fascism' essay

Yeah kind of but not really. We use socialism to mean lower phase communism, and full automation isnt necessary to reach communism, although they definitely go hand in hand.
Chapter 5 of State and Revolution might be of interest, particularly the last section.
marxists.org/archive/lenin/works/1917/staterev/ch05.htm

Every state is a tyranny. Authoritarian socialist states aren't objectively any less "democratic" than Liberal republics, and, in most times, much more.

The reason Ur-fascism was written was probably for the ultra-left bludgeon against actually existing socialism. Western leftists loved nothing more than spitting on the USSR.

20th century socialism was based in plenty of ways, but let’s not pretend they were democracies in practice (not to say the western countries are either). Not because of their repression of actual countrrevolutionaries (ie not Trot boogeymen) but because of their ossified and unaccountable elite that ended up killing the Union.

Democracy really seems as utopian as full communism, in the near future at least. There has never existed an "actual" democracy in the past.

they were pared down democracy where groups ceded individual votes to a chosen vanguard representative in the form of the party which is an economic and political union.
mind you, the flaw is that they didnt have the ability to undo dictatorship of proles via referendum nor did they have a right to recall their representatives (like cuban democracy for example) but still getting bogged down in idealistic definitions of democracy discounts that even pure democratic forms have abusive/coercive potentials and are also authoritarian (all government is always authoritarian). the only exception would be utopian communism, where no violence by the state or the masses ever happens and the population is single minded because of complete lack of hierarchy
i dont think most of the USSR wouldve voted to get rid of the leadership anyways. so thats a success in my estimation; the journey doesnt matter, just the destination… and the destination is the peoples desired outcomes.
that sounds no different than most western capitalist democracies so if your measuring stick is bourgeois western democracy yes they were not all that different but by more left standards of democracy, its only existed in a handful of countries in all of human history and that list doesnt have china or russia in it.

read about authoritarian mentalities more than just eco. like adorno:
archive.org/stream/THEAUTHORITARIANPERSONALITY.Adorno/THE AUTHORITARIAN PERSONALITY. -Adorno_djvu.txt
there is more to fascism than just economics and state craft. see above where former reactionaries use terms of disgust: disgust reactions and parsing the other/outgroup as rats or pestilences/diseases to be cleansed is a backwards holdover mentality that helps to produce and be capitalized on in recruiting reactionaries. there used to be a lot more psychopaths in the world. they used to be adaptation-wise, valuable for protecting children and women (through their psychopathic possessiveness and capacity for violence). nowadays, theyre not so useful since society is a lot more built around more pacifistic activity.
reactionaries are creatures of dead or dying structure and hierarchy rather than capable of creative improvisation and rebellious critique of the status quo. all states have conservative elements; but then again the bolsheviks and maoists were creative for their time, capable of improvisation and refinement. they were dynamic. did the average peasant have reactionary thoughts, yeah sure. then again they also had the political opportunity to progress society by killing and terrorizing their oppressors. authority isnt so bad when its keeping you from starving or helping you learn how to read for the first time. so what authoritarian elements you see are by nature… not fascistic. red terror is simply not comparable. theres more to be argued about that red terrors and the like are by nature utilitarian and forced by necessity, whereas fascists play at genocide and terror for idealistic, superstitious compulsive/neurotic reasons. thats why it always costs too much for them: red terrors and gulags and the like wouldnt exist if they were terribly inefficient.
authoritarian isnt a profane word. its not an insult all the time. it means what it means when it does.

Really? Like where?

Democracy isn't a binary, as you yourself has mentioned, Democracy isn't a system of institutions, but a property of society. It is on a scale, and China and Russia were fairly democratic, at least in several few years right after the victory in the Civil War.

Overall, there has never existed an institution that would strengthen democracy. All institutions, otherwise, weaken it. And authoritarian Socialist states weaken it less, because at least they do not conceal their true nature - or at least - do not make much effort to conceal it for internal needs. Whereas the Liberal Republics aim to completely discredit any idea of democracy, and make everyone believe that Democracy is percicely the Liberal institutions and nothing else.

You still need institutions though, and plenty of authors wrote about how those institutions would differ from bourgeois democracy (soviet vs parliament etc). Democracy can’t function without direct legal means by which the citizens can influence the state, even against the wishes of those administering the state. Otherwise what prevents the state from acting independently or against people’s wishes?

Direct and constant pressure, with a promise of violence, from the people. Nothing else really can. All your institutions will be subverted by the established power one way or the other.
Of course, the last great attempt to achieve democracy - the Cultural Revolution - has also failed.

Thus we come to Communism - a dictatorship that allows some struggle for the Labour rights, and is efficient in managing the state and developing productive forces.

Anarcho-Tankism